Dissertation (MSc Information Technology) ROMAN NUMBER ERRORThe aim of the study was to evaluate the service performance of Fund Management Information System (FuMIS) of Zanzibar Social Security Fund (ZSSF). The data were collected by using questionnaires, interviews, technical documentary reviews and system analysis when the system users interacted with the system. The study examined the level of users‟ satisfaction on data accessibility from the system, response time, usability of computer applications and the system interfaces, as well as the availability of the system services. The findings showed that, majority of respondents were satisfied with the system services. The study findings identified a number of factors influencing the FuMIS system service performance. These included security, network delay and response time, network connectivity, system misbehaviour, errors in data processing and keeping the customer‟s records. The study found that there were challenges in data access and system‟s services availability, especially in remote access. The study also found that there was system users‟ workload during updating the customers‟ records at the data entry section. Moreover, the study revealed that the main causes of these problems were: remote static routing configuration; insufficiency of data cleaning tools whereby the manual procedures were mostly used for data error inspection, power outage, network or device failure; as well as lack of distributing processes between customer-care and their records updating processes. The study recommends that it is important for ZSSF to have redundancy routing between sites and database replication. These will reduce network delay by reducing the number of remote access and there will be no single out point of failure between the sites. It is also important to have automatic data cleaning tools for error inspection, users‟ workloads management by increasing parallel processing at data entry unit.