The idea of teacher development has gained considerable attention in teacher education. Thernfact that it has been only marginally treated in the M.A TEFL research at Addis AbabarnUniversity provided the impetus to study it. The purpose of the present study was to explorernthe developmental nature of the experienced English language teachers in the senior secondaryrnschools of Addis Ababa. The study was carried out, specifically, to investigate the actualrnteacher development practices, the teachers' views of the various developmental activities,rnfactors hindering teacher development efforts and anticipation of future developmentalrnpursuits.rnTo conduct the study, a descriptive research approach was employed. The data used inrnthe study were generated through questionnaires and interview. Thirty-six English teachersrnand six principals in the selected six government and non-government senior secondaryrnschools of Addis Ababa were involved in the study.rnVarious statistical techniques and procedures of data analysis were used. To analyzernthe descriptive data, frequency distributions, percentages and average scores were used. T-testrnand Chi-square (X2) analyses were made to detect the difference between the two groups ofrnteachers with regard to their developmental experiences and views. To analyze writtenrnresponses and reflections in the interview part of the study, content analysis and guidedrnanalysis procedures were applied.rnGenerally, the study revealed that in both government and non-government schoolsrnunder study, teaching English is an isolated practice. Conditions within which collaborativernlearning can be optimized have not been sufficiently provided in both groups of schools. Onrnthe other hand, the results suggested that the teachers would like to improve themselvesrnthrough learning in their profession and appreciate the various developmental activities inrnschools and administrative roles that may facilitate conditions within which individual andrncollective learning can be optimized. The implications of the findings for the schools and thernteachers were presented and discussed Recommendations for further study were also made.