The professionalism of teachers through collaboration has become increasingly important in the last years. This paper describes the process of designing and validating a questionnaire for the analysis of future Primary and Pre-school teachers' collaboration patterns. The psychometric properties of the scale were obtained from the analysis of the validity of content (expert judgement and pilot test to 293 students of Primary Education and Pre-school Education at a Spanish university and from construct (factor analysis) and reliability (Cronbach Alpha), obtaining appropriate results (KMO = 0.89; CFI = 0.91; GFI = 0.95; AGFI = 0.96; SMSR = 0.05). Four factors were identified in the questionnaire on collaboration and shared professional learning: Assertiveness and personal willingness to work together, Group Cohesion, Leadership Capacity and Group Awareness. The results obtained are consistent with empirical studies carried out on the teachers' willingness towards collaboration, ongoing training and teacher professional development.