Background: Long acting injectable antipsychotics (LAI-APs) are considered a major advance in psychiatric treatment concerning treatment adherence and outcomes. Yet, both, doctors and patients remain sceptical. Aim: To explain the rationale for using LAI-APs, review their effectiveness and explore barriers to use. Method: Clinical overview of LAI-APs from the patient and doctor’s perspective. Results: LAI-APs were developed to increase adherence to treatment, thereby improving treatment outcomes. LAI-APs may reduce the risk of relapse and hospitalisation. Yet, the evidence from the few meta-analyses available remains weak. Both patients and doctors may associate LAI-APs with stigma and coercion. Current means of improving adherence include more focus on the therapeutic relationship, better information, adverse effects minimisation and half-life extension of LAI-APs. Future means of improving adherence include novel administration techniques that abolish the need for injection. Conclusions: For both, clinicians and drug developers, drug adherence remains a major target for improving treatment outcomes.