Abstract: We develop variations of the M|G|1 queue to model the process of software maintenance within organizations and use these models to computer the optimal allocation of resources to software maintenance. User requests are assumed to arrive following a Poisson process and a binomial distribution is used to model duplication of request. We obtain expressions for expected queue lengths with an exponential server using a N-policy for an integer N greater than or equal to 1. We also obtain the optimal batching size and mean service rate by minimizing the total cost consisting of the cost of the server, the cost of waiting, and the fixed cost of maintenance, if applicable.