Acquired chemotherapy resistance remains a significant barrier to curative treatment in many cases of advanced cancer.   It is hypothesized that underlying cell-cell competition between chemotherapy sensitive and chemotherapy resistant cell populations may drive tumor progression and eventual treatment resistance.  In these cases, adaptive therapy, whereby a chemotherapeutic agent is given intermittently based on growth parameters, has been proposed to exploit intra-tumoral cell-cell competition and delay resistance development.  When compared with standard chemotherapy administration schemes, adaptive dosing schemes often delay the competitive release of the resistant cell population by maintaining the sensitive population within the tumor.  In this talk, a modified Lotka-Volterra model for analyzing adaptive therapy will be described as well as a region within parameter space where extinction of the resistant population is achievable.  It will be shown that optimal model behavior can be examined using analytical techniques in order to directly compare adaptive therapy with continuous dosing schemes