In this thesis we present three original algorithms which solve the distributed mutual exclusion problem. Two of the three solve the problem of allowing only one site at a time into the critical section. The third solves the more difficult problem of allowing a specific number of sites (k sites) into the critical section at a time; All three algorithms are Token Based . That is, they make use of a token and token queue in order to guarantee mutual exclusion. Only the site that currently has the token is allowed to enter its critical section in the 1 mutual exclusion algorithms. Only the sites that have seen the token, since they requested it, are allowed to enter their critical sections in the k mutual exclusion algorithm; The primary goal of our algorithms is efficiency. Both of our 1 mutual exclusion algorithms require between 2 and n messages per critical section (n being the number of sites) depending on the number of requests for the critical section. Our k mutual exclusion has similar requirements between 3 and n messages per critical section depending on the number of requests for the critical section. (Abstract shortened by UMI.)