<![CDATA[Teachers' performance is influenced by transactional leadership and principal supervision, as well as teachers' work motivation. This study aims to analyze the influence of Interpersonal communication and work environment on teacher performance with the mediation of job satisfaction. This study employs a quantitative method with a survey technique. The research population is all junior high school (SMP 6) teachers, Cilegon City. The research sample was determined using a proportional stratified random sampling technique with strata based on the level of teacher education. Data was collected using questionnaires that have been tested for validity and reliability. The data obtained was analyzed using descriptive and inferential statistical techniques. Based on the results of the validity and reliability tests, all research instruments used in this study, namely the instruments for measuring the variables of Performance (Y), Transactional Leadership (X1), Supervision (X2), and Work Motivation (Z), have met the requirements. All items in each instrument have a calculated r value greater than the r table value (0.1816), indicating that all items have a significant correlation with the variable being measured, so that the instrument is considered valid. In addition, all instruments have an Alpha coefficient value greater than 0.8, indicating that the instrument has a high level of reliability, so that the measurement results can be trusted and consistent. Thus, the research instruments used in this study can be said to be valid and reliable, so they are suitable for use in research to measure the predetermined variables.]]>
