Despite a long history of urban planning, Kenyan towns are still characterized by informality, uncoordinated development, urban sprawl, and congestion. Government documents and reports acknowledge that, despite planning, no deliberate effort has been made to implement plans. Little is known about what impedes plan implementation in Kenya. This study sought to develop an in-depth understanding of the barriers to plan implementation from the perspectives of public officials responsible for planning. Using path dependency theory, forwarded by Pierson, and force field analysis, advanced by Lewin, the research questions focused on legal and institutional development, as well as on the nature of relationships between different actors as possible sources of hindrances to plan implementation. Data for this qualitative study accrued through reviews of documents relating to urban planning and interviews with officials in different categories, with a focus on three case cities: Nairobi, Nakuru, and Eldoret. A total of 14 participants, 10 from the city level, included county legislators; 4 from the national government level were interviewed. The data obtained were analyzed qualitatively using multiple-level coding and direct interpretation to create themes. The themes that emerged included politics and vested interests, financial, legal regime, institutional setup, land tenure, and quality of the plans. Study findings may be useful in informing planning authorities on how to restructure the preparation and implementation of urban plans.