Abstract: This paper highlights the pragmabehavioral errors in English used by Kimeru L1 secondary school students. The study proceeded on the premise that pragmatic competence of Kimeru L1 learners of L2 English was previously unknown prior to this study because of lack of in-depth research in this area. Using a descriptive research design and a sample of ninety respondents the researchers isolated errors in apology as well as request and permission making and documented the seriousness of these errors. The main objectives of the study were to examine pragmabehavioral errors, their effects and causes and possible areas of intervention. The study was guided mainly by Murcia’s [1] Model of pragmatic competence. The sample was drawn from three selected CDF secondary schools in Meru Central Sub-county, Meru County. The main instruments of data collection were: a discourse completion test, a classroom debate, observation schedule, and a teacher questionnaire. Results indicate that kinesics, proxemics and voice modulation errors are grave among the subjects. These results are hoped to immensely benefit second language pedagogy, education policy makers, teachers and learners of English.