220 F.3d 532 (7th Cir. 2000)
DARLA J. BOURELLE and RHONDA WENDLING, Plaintiffs-Appellants,v.CROWN EQUIPMENT CORPORATION, Defendant-Appellee.
No. 99-3981
In the  United States Court of Appeals  For the Seventh Circuit
Argued May 30, 2000
Decided July 17, 2000

Appeal from the United States District Court  for the Central District of Illinois.  Nos. 95 C 2065 and 95 C 2256--Harold A. Baker, Judge.
Before POSNER, Chief Judge, COFFEY and KANNE,  Circuit Judges.
COFFEY, Circuit Judge.


1
After Rhonda Wendling and  Darla Bourelle were injured in the course of  their employment at Sears Logistical Systems  (SLS) in Manteno, Illinois, they both filed  product liability and tort actions in the  Illinois state court system. In their complaints,  the two women alleged that the Crown Turret  Stockpicker (TSP)1 that they were operating,  and which was manufactured and placed in the  stream of commerce by Crown Equipment  Corporation, was improperly designed. They also  alleged that Crown was negligent in its  maintenance of the TSP, as well as the  operational warnings it provided for the  forklift. Based on the diversity of the parties,  Crown removed the two cases to the United States  Federal Court for the Central District of  Illinois. After the trial judge ruled that the  plaintiffs' expert witness, Daniel Pacheco, was  "unreliable" within the meaning of Fed. R. Evid.  702,2 he granted summary judgment to Crown on  the plaintiffs' product liability claim.3 We  affirm.4

I.  BACKGROUND
A.  The Accidents

2
Because this case turns on the reliability of  the plaintiffs' expert witness and not on the  nature nor the cause of their injuries, we need  not undertake a long discussion dealing with the  facts of the plaintiffs' respective accidents.  Suffice it to say, Wendling was transporting  empty pallets which were stacked on the forks of  the TSP directly in front of the operator's  compartment. As the TSP was traveling along the  wire system down a narrow warehouse aisle, a  pallet became dislodged, hit the side of the  aisle, entered the operator's compartment, and  violently struck Wendling in her abdomen.  Bourelle was injured while operating the same TSP  that was involved in Wendling's accident; she was  also transporting empty pallets down a narrow  warehouse aisle when a pallet entered the  operator's compartment and struck her left knee,  necessitating surgery.

B.  The Expert

3
The plaintiffs' proposed expert, Daniel Pacheco,  is a mechanical engineer with experience  investigating lift truck accidents. He received  his B.S. degree in mechanical engineering from  the University of Massachusetts in 1964, and his  M.S. degree in management from the Graduate  School of Management in Lake Forest, Illinois, in  1974. Additionally, Pacheco has been a registered  Professional Engineer in Illinois since 1970, and  was employed for seventeen years as an engineer  for Fiat-Allis Construction Machinery Inc. of  Deerfield, Illinois, and Pettibone Corporation of  Chicago, Illinois, working on the product design  and the development of heavy vehicles and  forklift trucks. In 1982, Pacheco became a senior  engineering consultant for Polytechnic, Inc. of  Lincolnwood, Illinois. In 1989, Pacheco became  president of Polytechnic, Inc., and now  specializes in the safety analysis of  construction and industrial equipment.5


4
Wishing to use Pacheco's expertise in their  suit, Wendling and Bourelle retained Pacheco, in  November 1998, as an expert witness to perform an  engineering investigation, and prepare a report,  concerning their two accidents.6 The trial  judge described Pacheco's investigation as  consisting of reading the depositions of the plaintiffs and ten  other people who had knowledge relevant to the  occurrences that are the subject of the suit. Mr.  Pacheco also reviewed Crown Equipment Corporation  manufacturing and service documents for the TSP,  Crown sales brochures, a training manual and  engineering drawings for the TSP.


5
On the basis of this investigation, Pacheco  opined that the TSP was defective both because it  was designed with inadequate guarding and because  it lacked an adequate warning regarding the risk  of pallets becoming dislodged and entering the  operator's compartment.7


6
Specifically, Pacheco stated that the wire mesh  guarding, covering the area between the lower bar  and the bottom of the operator's compartment,  could be (and should have been) extended up to  the mid-bar, and that such guarding would have  prevented Bourelle's injury. Pacheco also opined  that the "same type of structure as utilized in  the overhead guard could be placed in front of  the operator's compartment on top of the  midrail," and that such guarding would have  prevented Wendling's injury. In short, Pacheco  would, as Wendling and Bourelle explain in their  brief, "extend the already existing guarding."


7
The district court found that although Pacheco  was qualified to testify as an expert witness,  his testimony was unreliable under Fed. R. Evid.  702 because


8
[h]is opinion as to guarding has not been tested  nor has any attempt been made to prove its  feasibility. He did not prepare engineering  drawings of his proposed design and undertook no  study of strength of materials necessary to  create the guards he proposes. His knowledge and  experience with TSP's is limited to his  examination of photographs and manufacturer's  literature. He has never seen one in operation in  the narrow warehouse aisles for which the TSP was  designed. The court can only conclude that Mr.  Pacheco's opinions about an unreasonably  dangerous condition in the TSP fall into the  category of subjective belief or unsupported  speculation.


9
The same can be said concerning his opinion  about the absence of a warning about colliding  with obstructions in the aisle and injury from  intrusion. . . . He has not designed a warning  for the TSP operator that would seek to  ameliorate the unsafe condition he believes  exists. It's just his opinion that common sense  would say that a warning would be appropriate.


10
The district court, after concluding that  Pacheco's opinions were not supported by  sufficient scientific evidence (that is,  Pacheco's lack of familiarity with both the  product in question and the setting in which it  was used), granted summary judgment in favor of  Crown on the product liability count.

II.  ISSUES

11
On appeal, Wendling and Bourelle contend that  the trial judge abused his discretion in  excluding Pacheco's expert testimony regarding  the allegedly defective design and labeling of  Crown's TSP.

III.  ANALYSIS
A.  Standard of Review

12
As the Supreme Court has stated repeatedly, we  review the district judge's decision whether to  admit or exclude expert testimony for an abuse of  discretion. See Kumho Tire Co. v. Carmichael, 526  U.S. 137, 119 S. Ct. 1167, 1176, 143 L. Ed.2d 238  (1999); see also General Electric Co. v. Joiner,  522 U.S. 136, 118 S. Ct. 512, 515, 139 L. Ed.2d  508 (1997). We are obligated to take cognisance  of the fact that deference to the trial court's  decision is the "hallmark" of abuse of discretion  review.


13
Clark v. Takata Corp., 192 F.3d 750, 756 (7th  Cir. 1999); see also Smith v. Ford Motor Co., 215 F.3d 713 (7th Cir. 2000). Furthermore, "[o]ur cases have recognized  the importance of testing in alternative design  cases," Cummins v. Lyle Industries, 93 F.3d 362,  368 (7th Cir. 1996), and "[t]he trial judge must  have considerable leeway in deciding in a  particular case how to go about determining  whether particular expert testimony is reliable."  Kumho Tire Co., 526 U.S. at 152; see also Ancho  v. Pentek Corp., 157 F.3d 512, 515 (7th Cir.  1998) ("It is well established that issues  related to expert opinion testimony are matters  of law to be determined by the trial judge."  (citations and internal quotations omitted)).

B.  The Reliability of Expert Testimony

14
In the recent and well-recognized Daubert v.  Merrell Dow Pharmaceuticals Inc., 509 U.S. 579,  589 (1993), the Supreme Court held that Fed. R.  Evid. 702 imposes on the trial court the  obligation, when dealing with expert witnesses,  to ensure that scientific testimony is "not only  relevant but reliable."8 In Kumho, the Supreme  Court clarified its decision in Daubert and held  that "this basic gatekeeping obligation" applies  to all expert testimony. 526 U.S. at 147. Thus,  the trial judge must determine whether Pacheco's  opinion was grounded in the "methods and  procedures of science," Daubert, 509 U.S. at 590,  and whether such testimony had sufficient  "factual underpinnings," Walker v. Soo Line R.R.  Co., 208 F.3d 581, 586 (7th Cir. 2000).


15
Furthermore, as the Supreme Court elaborated


16
The objective of [Daubert's gatekeeping]  requirement is to ensure the reliability and  relevancy of expert testimony. It is to make  certain that an expert, whether basing testimony  upon professional studies or personal experience,  employs in the courtroom the same level of  intellectual rigor that characterizes the  practice of an expert in the relevant field.


17
Kumho, 526 U.S. at 152. Also, "[i]t is axiomatic  that proffered expert testimony must be 'derived  by the scientific method[.]'" Clark, 192 F.3d at  756 (citations and internal quotations omitted).


18
In this case, the plaintiffs' expert surmised  and claimed that an alternative design should  have been implemented for the TSP, and if it had,  neither of the plaintiffs would have been  injured. However, when questioned by Crown's  counsel, Pacheco admitted that he had not done  any scientific testing to support his alternative  design theory. In his deposition, Pacheco stated


19
Q. Have you done any type of engineering testing  to verify if your alternative design that you  just described for us would eliminate the hazards  that you claim exist?


20
A. I haven't done any testing, no. . . .


21
Q. Have you attempted to replicate the application  of the TSP with this alternative design that you  advocate? Have you done any studies to show that  you could perform these applications with a  barrier guard in front as you just described?

A. I haven't done any studies.9

22
Also in his deposition, Pacheco admitted that he  has not prepared "detailed design or  calculations," performed "an economic feasibility  study," prepared "preliminary design drawings,"  or performed "any risk utility type testing." The  district judge stated that without such work or  testing, "[t]he court can only conclude that Mr.  Pacheco's opinions about an unreasonably  dangerous condition in the TSP fall into the  category of subjective belief or unsupported  speculation."10 Cf. Clark, 192 F.3d at 759  ("Where the proffered expert offers nothing more  than a 'bottom line' conclusion, he does not  assist the trier of fact." (citing Rosen v.  Ciba-Geigy Corp., 78 F.3d 316, 318-19 (7th Cir.  1996))).


23
On appeal, Wendling and Bourelle contend that  the district judge "failed to be flexible" in  determining the reliability of Pacheco's opinion.  They argue that "[a]lthough Pacheco may not have  satisfied the specific factors delineated in  Daubert, he did meet enough reliability factors  to render his opinion admissible." That is,  although Wendling and Bourelle concede that  Pacheco has failed to perform any studies or  testing of his proposed design and further  acknowledge that their proposed expert never  observed the TSP forklift in question (much less  saw a loaded TSP operate in the narrow aisles of  a warehouse), they contend that "[t]he necessity  for testing is diminished" because "Pacheco is  relying on the testing already performed by  Crown."11


24
However, the appellants ignore the fact that Pacheco never:


25
1) saw or inspected the vehicle  itself (only pictures and videotape); 2) never  observed the vehicle loaded and operating within  the narrow confines of the warehouse; 3) prepared  any drawings in relation to his alternative  design theory; 4) conducted any computer  analysis; 5) submitted his alternative design  theories to the American National Standards  Institute (ANSI), despite the fact that he was  aware of the organization; nor 6) had any  recognized scientific approval of his alternative  design theories. Furthermore, as the appellants  admit, Pacheco did not satisfy the specific  factors delineated in Daubert. And, although  courts should be flexible in their application of  Daubert, there is no requirement that judges  apply only those criteria that the plaintiffs  believe are important. See Ancho, 157 F.3d at  515.12


26
In this case, the trial judge focused on the  lack of testing performed by the plaintiffs'  expert and concluded that without such testing,  Pacheco's opinions were nothing more than  speculation and were thus unreliable. Recognizing  that "[t]he trial judge must have considerable  leeway in deciding in a particular case how to go  about determining whether particular expert  testimony is reliable," Kumho Tire Co., 526 U.S.  at 152, and that testing is important in  alternative design cases such as this, see  Cummins, 93 F.3d at 368, we are of the opinion  that the judge did not abuse his discretion in  excluding Pacheco's testimony as unreliable. This  conclusion is bolstered by the fact that  Pacheco's opinion is also unreliable under the  other factors delineated in Daubert  no lab or  organization has tested his theories; no other  manufacturer incorporates his proposed design;  and he has not seen any industry studies  regarding accident experience with the TSP. See  generally General Electric Co. v. Joiner, 522  U.S. 136, 146 (1997) ("[N]othing in either  Daubert or the Federal Rules of Evidence requires  a district court to admit opinion evidence which  is connected to existing data only by the ipse  dixit of the expert. A court may conclude that  there is simply too great an analytical gap  between the data and the opinion proffered.").


27
C. Pacheco's Expert Opinion Regarding a Warning  for the TSP


28
As stated above, Pacheco also opined that the  warning labels on the TSP were inadequate because  they failed to provide an adequate warning  regarding the risk of pallets becoming dislodged  and entering the operator's compartment.13  Specifically, in his December 1, 1998 report,  Pacheco stated that this warning was inadequate  and that "Crown failed to adequately warn of the  hazards and warn of necessary operational steps  to be taken which would enable users to avoid the  hazard."


29
The same reliability requirements that apply to  alternative design apply to alternative warnings.  See Cummins, 93 F.3d at 367. Just as Pacheco  failed to test his proposed guarding  requirements, Pacheco also failed to test (or  even to draft) an alternative warning for the  TSP. At his deposition, Pacheco testified


30
A. I think there needs to be a specific warning to  the operator about this particular hazard.


31
Q. The hazard of pallets possibly entering the  compartment?


32
A. Yes.


33
Q. And what kind of warning would you provide to  so satisfy your belief one ought to be provided?


34
A. You mean the language of a warning?


35
Q. Yes, yes.


36
A. I haven't created the language for a warning,  so I would have to do that.


37
Q. So you haven't done that task?


38
A. That's right.


39
* * *A. You're not going to get the answer because I  told you I have not drafted a warning. But that  is the subject of the warning, is [sic] the  hazard.


40
Q. You can't, as you're sitting here today, give  me the gist of the warning, the language that you  would employ?


41
A. Correct.


42
Thus, like his proposed design, Pacheco's failure  to even draft a proposed alternative warning for  the TSP's operation manual renders his opinion  regarding the alleged inadequacy of Crown's  existing warning concerning the risk of pallets  entering the TSP operator's compartment to be  unreliable. See, e.g., Jaurequi v. Carter Mfg.  Co., Inc., 173 F.3d 1076, 1084 (8th Cir. 1999)  (Excluding expert testimony that "warnings were  deficient in placement, design, orientation, and  content" as unreliable because "[n]either  [expert] had created or even designed a warning  device which would have been more appropriate,  much less tested its effectiveness.").


43
The district judge's decision to prevent  [Pacheco] from testifying, far from being an  abuse of discretion, see General Electric Co. v.  Joiner, 522 U.S. 136 (1997), was absolutely  correct. Many times we have emphasized that  experts' work is admissible only to the extent it  is reasoned, uses the methods of the discipline,  and is founded on data. Talking off the cuff--  deploying neither data nor analysis--is not  acceptable methodology. See, e.g., McMahon v.  Bunn-O-Matic Corp., 150 F.3d 651, 657-58 (7th  Cir. 1998); Mid-State Fertilizer Co. v. Exchange  National Bank, 877 F.2d 1333, 1339 (7th Cir.  1989).


44
Lang v. Kohl's Food Stores, Inc., 217 F.3d 919 (7th Cir. 2000).  The fact that Pacheco never even drafted a  proposed warning renders his opinion akin to  "talking off the cuff" and not acceptable  methodology. Accordingly, we conclude that the  district judge did not abuse his discretion in  excluding, as unreliable, Pacheco's opinion  regarding a warning for the TSP.  The decision of the district court is


45
AFFIRMED.



Notes:


1
 According to the district court,
[a] TSP is a forklift truck designed to move full  pallets in and out of warehouse racks and also  for order picking partial loads. The turret on  the TSP allows the operator to work either side  of a narrow warehouse aisle without turning the  truck around. The TSPs in this case were operated  in the warehouse aisle on an electronic wire  guidance system. The operator controls the speed  and direction of the TSP's movement but not the  steering. That is controlled by the wire. The TSP  is a "man-up" forklift, i.e. the operator's cab  elevates so that she is in close proximity to the  work being performed.


2
 Fed. R. Evid. 702 states
"If scientific,  technical, or other specialized knowledge will  assist the trier of fact to understand the  evidence or to determine a fact in issue, a  witness qualified as an expert by knowledge,  skill, experience, training, or education, may  testify thereto in the form of an opinion or  otherwise."


3
 Rather than proceed with their negligence claim  in the district court, Wendling and Bourelle  voluntarily dismissed the negligence count  without prejudice, and filed a notice of appeal  from the district court's order granting summary  judgment for Crown on the product liability  count. In an order dated November 24, 1999, this  court expressed concern that the parties'  stipulation to dismiss the negligence count  without prejudice "manufactured a final judgment"  and did not make the district court's summary  judgment order final and appealable within the  meaning of 28 U.S.C. sec. 1291. Subsequently, the  parties stipulated to dismiss the negligence  count with prejudice, and this appeal was allowed  to proceed.


4
 We note that this court recently decided another  case involving Crown and Pacheco, see Weir v.  Crown Equipment Corp., 217 F.3d 453 (7th Cir. 2000), however these  cases were not consolidated because they involved  different types of forklifts and arose in  different states.


5
 In 1993, Pacheco co-authored a paper, Risk  Analysis of Forklift Drivers.


6
 At oral argument counsel for Wendling and  Bourelle explained that a previously retained  expert became ill, and that Pacheco was a last  minute substitute.


7
 Pacheco stated his opinion on three separate  occasions
1) in an engineering investigation  report dated December 1, 1998; 2) in his  deposition taken January 7, 1999; and 3) in an  affidavit dated September 24, 1999.


8
 Daubert set forth the familiar nonexhaustive list  of four factors that are helpful in gauging the  reliability of expert testimony
1) whether the  theory is scientific knowledge that will assist  the trier of fact and can be tested; 2) whether  the theory has been subjected to peer review or  publication; 3) the known or potential rate of  error and the existence of standards controlling  the technique's operation; and 4) the extent to  which the methodology or technique employed by  the expert is generally accepted in the  scientific community. See Daubert, 509 U.S. at  593-94. However, [b]ecause the Daubert Court "emphasized that it  did 'not presume to set out a definitive  checklist or test,' and that the district judge's  inquiry should be 'flexible,'" United States v.  Vitek Supply Corp., 144 F.3d 476, 485 (7th Cir.  1998) (citation omitted), there is no requirement  that the district judge consider each one of  these "guideposts" when making an admissibility  ruling under Fed. R. Evid. 702.
Ancho, 157 F.3d at 515.


9
 In his December 1, 1998 report, Pacheco  recognized that "[i]n the stockpiling operation,  the standing operator has a need to access racks  outside the periphery of the truck and place  loads onto the pallets in front of the operator's  compartment without interference by fixed barrier  guards between the compartment and the forks."  (Emphasis added).


10
 The judge did not impose testing as an absolute  requirement. Pacheco's opinion is not reliable on  any of the other Daubert factors. In his  deposition, Pacheco admitted that no lab or  organization has tested his theories, that no  other manufacturer incorporates his proposed  design, and that he has not reviewed any industry  studies regarding accident experience with the  TSP.


11
 Wendling and Bourelle also contend that Pacheco's  experience "is an important factor in determining  the reliability of his opinions regarding the  necessity of guarding on the TSP . . . [and] the  District Court should have given it more weight."  But this argument is misconceived because it  fails to take into account the fact that this  court treats the reliability of an expert's  opinion in a particular case separately from his  or her overall qualifications. See Clark, 192  F.3d at 759 n.5 (7th Cir. 1999)  ("[Q]ualifications alone do not suffice. A  supremely qualified expert cannot waltz into the  courtroom and render opinions unless those  opinions are reliable and relevant under the test  set forth by the Supreme Court in Daubert.");  Kirstein v. Parks Corp., 159 F.3d 1065, 1067 (7th  Cir. 1998) ("It is true that Dr. Nelson has  impressive credentials. . . . But the fact is  that he did no testing on these products . . . .  And we have sanctioned the exclusion of  speculation offered by persons with credentials  as impressive as those of Dr. Nelson."); Minasian  v. Standard Chartered Bank PLC, 109 F.3d 1212,  1216 (7th Cir. 1997) (Warning that "judges not be  deceived by the assertions of experts who offer  credentials rather than analysis.").


12
 As we stated in Clark, 192 F.3d at 759, [g]iven the state of the record, including the  absence of any stated methodology, it is  difficult for this Court to evaluate the  scientific technique used by Dr. Lafferty in  formulating his opinions. Thus, we sympathize  with the trial judge's inability "to determine  [if the] methods are consistent with the  generally accepted method for gathering and  evaluating evidence in the field of biomechanics  and mechanical engineering as applied to occupant  dynamics and restraint system efficacy in motor  vehicle accidents." Dr. Lafferty's second  opinion, that a properly functioning lap belt  would have prevented Clark from moving upward  four inches and striking the roof of the vehicle,  lacked reliance on any 'stated methodology' or  the scientific method.
See also Ancho, 157 F.3d at 517 ("There is  nothing in the record that would cause us to  believe that Lobodzinski presented any  architectural designs or materials to illustrate  his proposals. Furthermore, as previously stated,  the judge pointed out that Lobodzinski had failed  to observe the transfer car in operation, much  less visit the accident scene, nor had  Lobodzinski ever observed any similar conveyor  system.").


13
 The TSP operator's manual, which both Wendling  and Bourelle admitted reading while training to  operate the TSP, states
"All clearances must be  checked before traveling due to various load  lengths, widths, and/or misalignment which will  affect load clearance."


