Abstract
The main purpose of the study was to determine the relationship between lead time and performance of manufacturing firms in Nairobi City County, Kenya. The study used descriptive research design, where both qualitative and quantitative research was applied. The target population will be 328 respondents from the concerned firms in Nairobi city county, Kenya. The researcher carried census survey since respondents are manageable. The research technique was purposive sampling techniques. 10% (33) of the respondents was pilot tested for validity and reliability of the research instrument. Data was analysed using descriptive statistics and inferential statistics with the help of Statistical Package for Social Science version 28 and the same is now presented in a form of tables and figure. The reliability and validity results was acceptable with rating of over 0.7 and 0.5 respectively. This study concludes and recommends that lead time had a strongly relationship with performance of manufacturing firms in Nairobi city County, Kenya.
Key Words: Lead Time , Performance , Manufacturing Firms , Nairobi City County, Theory of Constraints