In 2015 the National Institute for Health and Care Excellence (NICE) updated its 2006 guideline to clarify the association between parent infant co-sleeping and sudden infant death syndrome (SIDS). The practice of co-sleeping is a topic of continuing controversy and debate. Rather than highlighting the risks, the emphasis of the NICE guideline is to provide parents with balanced information so that they can make informed decisions about where their babies sleep. This contradicts previous public health messages on co-sleeping that discourages parents from the practice. Consequently, the updated national guideline has been criticised for failing to provide parents with safer sleep information, which has led to widespread confusion for parents and professionals. Health professionals can deliver safer sleep advice to support parents in their decision-making. However, as a result of inconsistent guidelines and evidence about parent-infant co-sleeping, health professionals may feel apprehensive and ill-equipped to provide advice and support. This article draws on a non-exhaustive literature review to discuss the risks and benefits of parent-infant co-sleeping, and the implications of this practice for SIDS. It also aims to provide transparency and improve understanding for health professionals so that they can support parents to adopt safer sleep strategies for their baby.