Access by small holder producers to seeds of improved bean varieties remains a constraint in many parts of the world. In response to this development challenge, this study examines the salient features of the Community Seed Bank (CSB) models implemented in Nicaragua from 2010 to 2014, through support from the Bean Technology Dissemination (BTD) project and analyzes the determinant factors contributing to their sustainability. CSB level data were collected from 154 CSBs through a survey and from project reports. Using the duration analysis technique, several determinants of sustainability mentioned in the available body of literature are confirmed. Namely, the CSBs that produce quality seed, recover seed production costs, have experienced leadership, operate formally as a group by documenting decisions, and have access to productive assets operate longer than CSBs that lack these characteristics. This study also confirms the importance of not only building seed production capacities of the CSBs but also seed marketing and administrative capacities. Seed marketing training was found to reduce the failure rate of CSBs that reported low seed yield in their first year of operation. Intensity of CSB operation was positively associated with increased risk of failure. Of the three types of CSBs implemented, individual seed banks failed 30% faster than CSBs administered collectively by community members. While the size of CSB membership did not impact time to failure, the CSBs that were more representative of the community did have lower failure rates. The study identifies important characteristics that should be considered in future promotions of community based or decentralized models of seed production of staple food crops such as beans.