Summary Risk factors linked to suicidal behaviour vary considerably by specific population and setting under study. This project is geared towards providing a better understanding of suicidal behaviour burden, its risk factors, its sociocultural perspectives and its associations with mental disorders in low- and middle-income countries (LMICs). We use a mixed methods approach to examine these factors in various settings. Specifically in chapter 2, we focus on factors associated with suicidal behaviour in persons with mental, neurological and substance use disorders. We use a systematic review and meta-analytic approach to examine these factors in a broader setting, low- and middle-income countries. In chapter 3, we specifically examine completed suicides in a community setting and narrow our study goals to the Kenyan population. In this chapter, we use a 5-year retrospective data from a health and demographic system in Western Kenya. Using this data, we estimate a cumulative incidence of definite suicides reported in the area. We further undertake content analysis of available verbal autopsies and additionally analyze for probable suicide incidence and factors associated with completed suicides in the western Kenya region. In the next chapter (4), we direct our attention to suicidal behaviour among general outpatients in the coastal region of Kenya. The study examines prevalence of suicidal behaviour in this cohort and further investigates factors associated with suicidal ideation in this cohort. In chapter 5, we narrow our focus on a cohort of patients diagnosed with psychotic disorders in the coastal region of Kenya. We prospectively recruit these patients from various psychiatric clinics and using a cross sectional survey design we examine factors associated with suicidal ideation and suicidal attempt. We analyze this data using both categorical suicidality outcomes and continuous risk score of suicidality outcomes. For the qualitative objectives of this thesis work, we focus on gaining an in depth understanding of how suicide is contextualized at the coastal region of Kenya and examine socio-cultural perspectives of suicide in chapter 6 of the thesis. In chapter 7, we explore perceptions on reasons for suicidal behaviour and community's recommendations for suicide prevention interventions in the area. For both chapter 6 and 7 we use individual in depth interviews from various key informants (persons with a history of suicidal attempts, bereaved family members, health care providers, community and religious leaders etc) to collect the data and thematic analysis technique to analyze the data. High prevalence of suicidality in the various settings (hospital and general population) and its strong link with mental disorders underscore the need for improving access to mental health care and routine screening for suicidality in health care settings. The exploratory qualitative research emphasizes suicidal behaviour as a complex multicausal human behaviour at the centre of which of lies a psychologically distressed individual. Increasing mental health literacy in our communities as well as decriminalizing suicide is key in destigmatizing suicidal behaviour and improving access to care for individuals in need.