The study was assessment of delay factors affecting success of commercial building projects in Rwanda: case of NITSAL International Construction, Epitome Architects Rwanda Limited and EPC Africa Companies. Data collection techniques were questionnaires, and documentary review; while methods of data analysis were descriptive statistical methods and linear regression analysis. Target population was 127 people while sample size was 96 respondents. Findings confirmed that there is a positive significant correlation between consultant related factors and clients’ satisfaction with (r= 0.076, p > 0.01). The findings revealed that there is a positive and low correlation between contractors related factors and cost performance with (r= 0.322, p<0.01); time performance with (r= 0.232, p<0.05); health and safety with (r= 0.250, p<0.05); functionality with (r= 0.320, p<0.01) for commercial building projects. The results revealed that there is a positive and strong correlation between technical equipment factors and cost performance with (r= 0.566, p<0.01); positive and low correlation between technical equipment and time performance with (r= 0.267, p<0.01); and health and safety with (r= 0.306, p<0.01); positive and strong correlation between technical equipment and functionality (r= 0.593, p<0.01) for commercial building projects. As conclusion, the objectives were realized, the research questions were responded; problem of the study was solved; research hypotheses were verified where all six null hypotheses were rejected by saying that there is different delaying factors affecting success of commercial building projects in Rwanda.
Key Words: Delay Factors; success, Commercial Building, Projects