AbstractCoroutines are routines which communicate with each other in a more general way than that provided by the normal subroutine mechanism. Although they have many potential applications, their use has been restricted by their lack of availability in common high‐level languages. This paper discusses some of the issues involved in implementing coroutines, and proposes an implementation written in Pascal which may be incorporated into a Pascal program to give coroutine facilities. Use of the system is illustrated by two solutions to the N‐Queens problem by different coroutine strategies. The basic system is then extended to allow more advanced use of coroutines.