You wouldn't do fixed prices at the "contract level", drill down further in FAR 12.207. The IDIQ is the master vehicle under which you would execute task orders that would allow you to use the exception in FAR 12.207( B )(1)(i)© to use T&M/LH pricing types which are cost reimbursement mechanisms. Remember that the exception applies to a "multiple award delivery order contract" so it implies that you would have to have more than one awardee. In addition, you also have contract documentation and other special requirements applicable to IDIQ contracts for commerical item procurements such as ceiling prices et cetera as seet forth in that section to consider. HOWEVER, if you are DoD, the DFARS limits what T&M/LH services you can acquire for support of commerical items. See DFARS 212.207 Out of curiosity, you mention you're acquiring "lab assistance, scientific data analysis, and other general laboratory work", are you funding this with O&M or are you RDT&E funded? Have you looked at whether this is Part 12 at all or should you be looking at Part 35? Bill