Based on the belief that professional competences can partially be developed through professional training a cycle of ten educational workshops was designed. Combining theoretical knowledge, quality practice examples and discussions, the workshops strived to improve professional teacher competences. The assumed outcome was determined by difference between initial and summative participants' self-evaluation results. Reliability of the "Teacher self-evaluation questionnaire" was determined through application of Cronbach's Alpha coefficient and is high regarding all scales (0.919 [is less than or equal to] [lambda] [is less than or equal to] 0.950). The sample is adequate and includes participants from both workshops cycles - global, held in United Kingdom and local, held in Croatia. The results of the empirical non-experimental research indicate that upon completion, in the second subsample, in which the workshops lasted for ten weeks, there was a statistically significant (p0.01) difference regarding teachers' self-evaluation of knowledge (t=-3.566) and skills (t=-3.316) for cooperation with parents compared to initial results. Neither sample exhibits a statistically significant difference regarding self-evaluation of attitudes. Teachers estimate that they have developed knowledge and skills necessary for cooperation with parents by the systematic training in a specific period of time which allows for verification and practice of learned skills. (author abstract)