Abstract: A critical component in monitoring and evaluation is planning, which is instrumental in providing the required guidance and support needed for performance. This study sought to investigate the role of partnership in planning and its effect on managerial performance in the Edmund Rice project in Mukuru Kwa Ruben, Embakasi sub-county, Nairobi, Kenya. A descriptive cross-sectional approach design was utilized as it is easier to observe ease in capturing the relationship between the existing variables. The target population was of directors, managers, accountants, employees, volunteers, and beneficiaries, which translated to a total of 380 participants. The stratified sampling technique was adopted in the selection of respondents based on their cadre. Thereafter, simple random sampling was incorporated until the sample was realized within the cadre. Descriptive statistics were determined through means, percentages, frequencies, and standard deviation. Inferential statistics were determined through correlation analysis and regression analysis. The level of statistical significance was set at p<0.05. Thematic analysis was used for the analysis of qualitative data. The findings showed that partnership planning had a significant association with the organization's performance (p < 0.014). ANOVA results revealed that partnership planning has an important influence on project performance, with an F-value of 0.007 and a p-value of 0.014. The qualitative data also revealed that partnerships are crucial processes in attaining the objectives of the organization. Partnerships in planning are crucial for performance through consultations among teams, strengthening open communication, which improves execution and collaboration. Further studies should explore how partnership in planning predicts on-time delivery of projects and whether the relationship is influenced by other factors. 

Key Words: Partnership, Planning, Managerial Performance, Capacity Building, Community-Based Organizations, Monitoring and Evaluation