The objective of this study was to inform Solomon Water of potential service delivery models for the expansion of water and sanitation services in informal settlements in Honiara. Currently, a range of water service delivery models are in use by residents of settlements. Solomon Water is currently expanding and improving its water and sanitation services in Honiara, and other regional towns urban center's. As a part of this improvement and expansion agenda, there is the opportunity to improve the water and sanitation services used by residents of informal settlements. In recognition of the diversity of environmental, social and economic diversity amongst urban residents in Honiara’s informal settlements, a range of water and sanitation service delivery models may need to be offered. This assessment identifies the range of possible water and sanitation service models, and, with input from Solomon Water, informal settlement residents and other stakeholders, together with analytical information and lessons about service delivery models used elsewhere, makes recommendations about the water and sanitation service options best suited to informal Honiara’s settlements.