There are visible challenges with employee development at Telkom Kenya where employees remain in one position for many years with some remaining in the same position until their retirement. Anecdotal evidence suggests that this problem could be linked to the design of the organization, but no systematic study has been conducted to ascertain this claim. This study, therefore, sought to determine the influence of work specialization on employee development at Telkom Kenya Nakuru Branch. The study was guided by the Axiomatic Theory of Organizations. It made use of the correlational research design where all the 51 employees of the Telkom Kenya Nakuru Branch were involved in the census study. Questionnaires were used to collect quantitative data from operational staffs while interview guides were used to gather qualitative data from heads of departments. Quantitative data were analyzed using frequencies, percentages, means, and the multiple regression techniques while qualitative data were analyzed using the thematic content analysis technique. Results showed that work specialization (β= 0.491, p=.000) had a statistically significant and positive influence on the development of employees at TKNB. Based on the findings, the study recommends that the management at TKNB should enhance work specialization by implementing job rotation programs and promoting a match between employees’ skills and their job.