Which of the following is NOT a type of indefinite delivery contract?

The concept of indefinite delivery contracts primarily concerns arrangements that do not specify a firm quantity of supplies or services to be delivered within a specific timeframe. These contracts are particularly useful in situations where the government cannot predict its exact needs and thus requires flexibility in delivery schedules.

A fixed-price contract, in contrast, is a distinct type of contract that does specify a set price for the goods or services provided, regardless of actual performance or delivery. This means that the contractor is obligated to complete the work for the agreed-upon price, which does not align with the indefinite nature of the other contract types listed. The primary characteristic of fixed-price contracts is their definitive nature regarding price and scope of work, making them inherently different from the indefinite delivery contract structure.

In contrast, definite-quantity, requirements, and indefinite quantity contracts all share a common thread of allowing for flexible quantities and delivery schedules, thus fitting within the broader category of indefinite delivery contracts. This flexibility is crucial for situations where demands are uncertain and variable, which is not a principle associated with fixed-price contracts.