This article examines Participatory Monitoring and Evaluation (PM&E) in community-based water projects implemented by the government and non-governmental organisations in Chamwino District. A sequential exploratory research design was adopted to collect quantitative and qualitative data employing a checklist of items, and a structured questionnaire. A random sample size of 120, water users was involved. The Mann Whitney U Test was used to analyse quantitative data while qualitative data were subjected to the content analysis. The results show that beneficiaries were involved in PM&E through ‘representation’ in governance structures including Village Water Committees, and Community Water Supply Organisations (COWSOs), and also through use of water agents, and direct involvement of individuals in different activities. Some activities like paying water charges and meeting maintenance cost, field visits and supervising project revenues were common for government and non-governmental projects while others like electing water committee members, labour and preparation of progress reports were specific for non-governmental projects. The extent of beneficiaries’ involvement in PM&E was 53.3%, with non-governmental projects showing higher beneficiaries’ involvement relative to governmental projects. The Mann Whitney U Test showed higher involvement of male relative to female respondents, and the difference was significant at 5% level of significance. The article concludes that PM&E was adopted in community-based water projects, more so in non-governmental relative to government water projects. There was an institutional arrangement of governance structures to enable PM&E by ‘representation’. Individual beneficiaries were also involved directly. The extent of involvement of beneficiaries was high among non-governmental projects relative to government ones. The article recommends the enhancement of PM&E in government projects to ensure realisation of project objectives.