The conditions for strategic health communication campaigns as a public health tool are examined for low-income contexts. The theoretical framework drafts a socioecological model with an extension of poverty influences to bring into focus the dynamics of a resource-poor environment and its impact on health-related behaviours and health campaigns. The research design includes two studies conducted in Sierra Leone. Study 1 triangulated three qualitative methods to explore past and current health communication practice in Sierra Leone. Study 2 is a mixed-methods field experiment on handwashing which explored the effects of different campaign strategies. Results show that a community-based participatory approach with the inclusion of local leaders as health messengers was associated with higher chances of behaviour change than a non-treated setting. Further pathways for context-sensitive approaches for deprived audiences are suggested.