The main purpose of this paper was to assess teacher preparedness in the implementation of the integrated Business Studies curriculum in public secondary schools in Kenya. Specifically, the study sought to: find out the level of preservice training of the Business Studies teachers implementing the integrated Business Studies curriculum and to find out the extent of in-service training of the Business Studies teachers implementing the integrated Business Studies curriculum. This study was based on the ideas and concepts of curriculum theorists; Gross et al., (1971), Tyler, (1949), Fullan (1982) and Shiundu and Omulando (1992), who noted that, for successful curriculum implementation, the degree of success depends on the extent to which several factors would be considered. The study employed a descriptive survey design. The study took a census inquiry and thus purposively collected data from all the Business Studies teachers and head teachers of all the public secondary schools in Nandi North Sub-County. Questionnaires for Business Studies teachers and interview schedule for head teachers were used to collect data. Validity of the research tools was determined by having experienced supervisors in the School of Education, Moi University who checked the questionnaires and the interview schedule, while reliability of the research instruments was established by a pilot study. Analysis of data was done using descriptive statistical techniques. The findings of this study revealed that Business Studies teachers were trained in the orientation of the old curriculum to teach Accounting, Economics or Commerce as separate subjects with majority having been trained to teach Economics and not Business Studies as an integrated subject while about a third of the teachers were untrained. Furthermore the study found out that majority 52 (71%) of the Business Studies teachers had never received any in-service training such as seminars and workshops. This study recommends that, there is need for Teachers Service Commission (TSC) to hire more professionally trained Business Studies teachers and organize more in-service training courses. Teacher training institutions should offer relevant training program in all areas of the integrated Business Studies subject. It is hoped that the findings from this study will be utilized by the Ministry of Education and other education stakeholders in order to come up with strategies that should be put in place to enhance the implementation of the integrated Business Studies curriculum in Kenyan secondary schools.