STUDY DESIGN Literature-based topic review. OBJECTIVE To review the complications and the concerns that may be associated with all of the commonly used osteobiologic options for spine fusion. SUMMARY OF BACKGROUND DATA Obtaining a solid arthrodesis is an important objective in many lumbar surgical procedures, and a wide array of bone graft materials may be used in an attempt to achieve this goal. Iliac crest bone graft, as well as all of the available osteobiologic alternatives, carries potential risks and concerns for both patient and surgeon. METHODS Review of literature and expert opinion. CONCLUSION Some of the potential complications associated with osteobiologic materials used in spinal fusion are well understood and clearly documented whereas others require further study and clarification. In any given clinical situation, the patient and surgeon need to balance the benefits and performance characteristics of the graft material with the risk profile to optimize clinical management.