OBJECTIVE: Affective psychoses and bipolar disorders have been neglected in the development of early intervention strategies. This paper aims to gather current knowledge on the early phase of bipolar disorders in order to define new targets for early intervention. METHODS: Literature review based on the main computerized databases (MEDLINE, PUBMED and PSYCHLIT) and hand search of relevant literature. RESULTS: Based on current knowledge, it is likely that an approach aiming at the identification of impending first-episode mania is the most realistic and manageable strategy to promote earlier treatment. During the period preceding the onset of the first manic episode, patients go through a prodromal phase marked by the presence of mood fluctuation, sleep disturbance, and other symptoms such as irritability, anger, or functional impairment. Additionally, various risk factors and markers of vulnerability to bipolar disorders have been identified. CONCLUSIONS: In the few months preceding first-episode mania, patients go through a prodrome phase (proximal prodrome) that could become an important target for early intervention. However, considering the low specificity of the symptoms observed during this phase, criteria defining high-risk profiles to first-episode mania should also include certain risk factors or markers of vulnerability. While more research is needed in high-risk groups (e.g., bipolar offspring), retrospective studies conducted in first-episode mania cohorts could provide valuable information about this critical phase of the illness.