<p>In this study an intervention program was implemented to develop pro-environmental recycling behavior among the students of a university, combining the strategies of information, social diffusion and prompts. There were three groups of participants. Each group attended two informative sessions. Afterwards, a group of students carried out social diffusion actions with their classmates. Prompts posted throughout the campus were also introduced. After the intervention there was a considerable increase in the number of PET bins with correct separation and in the amount of PET recycled. Also, there was a statistically significant increase in the awareness of recycling consequences and feeling of annoyance for not recycling in one group. In another group there was also a statistically significant increase in the feeling of annoyance.&nbsp;</p>