 This is a Phase 1, open-label, multicenter study evaluating the safety and PK profile of ABT-199 under a once daily dosing schedule. Two arms will be implemented for dose escalation: Arm A, CLLSLL subjects and Arm B, NHL subjects. Arm A is designed to enroll approximately 116 subjects with relapsed or refractory CLL or SLL and Arm B is designed to enroll approximately 95 subjects with relapsed or refractory NHL. Fifty-six subjects were enrolled in Arm A and approximately 55 subjects will be enrolled in Arm B during the dose escalation portion of the study, with the objective of defining dose limiting toxicities DLTs and the MTD. Once the MTD is declared for the arm, approximately 60 additional CLLSLL subjects in Arm A and approximately 20 additional DLBCL subjects and 20 additional follicular lymphoma subjects in Arm B will be enrolled in an expanded safety portion of the study at the recommended phase 2 dose RPTD and schedule. 