This paper search to present the main conclusions of a study that seeks to analyse and clarify the following issue: what is the predictive efficacy of psychological constructs and of sociodemographic variables in teachers' job satisfaction? Based on a sample of 752 Portuguese teachers working in 20 schools of the Zona Oeste, and using the hierarchical regression model, our results lead us to the global conclusion that psychological variables (such as self-esteem, intrinsic motivation, locus of control, sense of autonomy and satisfaction with life in general) have more predictive power than the socio- demographic variables (such as sex, age, duration of teaching experience or level taught) in analysing teacher job satisfaction. As regards the practical implications, it should be noted that the findings give great relevance to the structuring of strategies for building and developing teachers' skills in terms of personality, which appear to be very important for adjusting better to the demands of the teaching profession and obtaining higher levels of job satisfaction.