D.C. Mun. Regs. tit. 19, r. 19-4324
Fixed-price contracts may provide for a firm price or, in appropriate circumstances, an adjustable price.
Fixed-price contracts with an adjustable price shall include a ceiling price, a target price or both. The adjustment in ceiling price or target price shall be adjusted only by inclusion of a clause, approved by the Procurement Executive that authorizes an equitable adjustment of the contract price under specific and stated circumstances.
A firm-fixed-price contract shall provide for a price that does not allow any adjustment in price on the basis of a contractor's cost experience during contract performance.
A firm-fixed-price contract shall be used for acquiring commercial products or services and shall be based on detailed specifications, definitive statements of work and when the CCO anticipates there will be adequate price competition.
D.C. Mun. Regs. tit. 19, r. 19-4324