PARP inhibition represents the dawn of precision medicine for treating prostate cancer. Despite this advance, questions remain regarding the use of PARP inhibitors (PARPi’s) for the treatment of this disease, including 1) how specifically do PARPi sensitive tumor cells respond to treatment, and 2) how does PARPi resistance develop? To address these questions, we characterized response to olaparib in sensitive LNCaP and C4-2B cells and developed two olaparib resistant derivative cell line models from each, termed LN-OlapR and 2B-OlapR respectively.