Vendors licencing and permit issuing is among the critical policy issues in the urban settings. This is due to the sensitivity of operating this kind of a business in urban areas where there are inadequate open spaces to run this business from. Vendors’ licencing guarantees vendors’ wellbeing and livelihood. It resolves issues of is permitted to do the business in the city, what kind of business and in what public space or part of the city. Various actors in Tanzania have made several initiatives of ensuring effective licencing and permit issuing for street vendors. Such strategies include the introduction of vending zones as well issuing of IDs for the vendors. Despite these initiatives, street vendors continue to experience problems related to licence and permit acquisition. This study aimed at investigating barriers to the licensing and permit issuing, implications of unpredictable licensing and vending process on vendor’s livelihood and vendors’ perceived solutions to unpredictability of the legalization process. The study was qualitative in nature, was conducted in Dar es Salaam with a sample of 79 respondents who were selected both randomly and purposively. The findings indicate that the exercise is constrained with inadequate and ineffective urban institution, vendors’ attitude and understanding, urban politics and dynamics and the influence of social groups. Further the study revealed that unpredictability of the vendors’ licensing and permit giving exercise have negative implication on human, physical, social, financial and environmental assets. Vendors suggested that formulation and proper implementation of national policy for vendors as well as improving inclusive decision making will help to improve and resolve unpredictability in the vendors licencing and legalization process in Tanzania.