2 Oxford Health NHS Foundation Trust, UK Aims: Clinicians increasingly recommend tilt-in-space (TIS) within wheelchair and seating prescriptions to reportedly prevent pressure ulcers; however, it is often unclear what the optimum tilt angle should be. This review aims to determine the use and effectiveness of TIS in seating systems. Methodology: A search of eight electronic databases was completed, namely, Medline, CINAHL, BNI, EMBASE, ASSIA, PubMed, OTDBase, and ISI Web of Science Conference Proceedings; using the keywords TIS, seating, wheelchairs, pressure ulcer, and pressure sores. Databases were searched for articles written in English between 2000 and the end of August 2012. Articles included primary research; TIS as the intervention; and had adult participants. Results: After removal of duplicates and application of inclusion criteria, 12 studies were eligible for this review. Findings show that TIS was used to manage pressure and fatigue, prevent sliding, aid skin perfusion, and facilitate user comfort. Conclusions: Reasons for using TIS will influence the degree of tilt required for the chair occupant; nonetheless, it remains difficult to specify either the optimum degree of tilt or the duration for use in TIS seating systems. In order to build an evidence base, clinicians need to be very explicit on their reasons for prescribing TIS.