Our research evaluates whether consumers’ environmental knowledge (EK), the degree of their knowledge and their relative engagement in the collaborative economy (CE) influences responsible consumption (RC). This was evaluated according to a consumer's willingness to buy or rent second-hand perinatal and infant clothes. Additionally, we have explored the role of Information and Communication Technology (ICT) in the relationship between the collaborative economy and RC. These relationships were tested using a sample of 307 parents from Spain and an Ordinary Least Squares (OLS) regression model. Our results revealed that both environmental knowledge and the parents’ previous experience in the collaborative economy condition their willingness to behave responsibly by buying or renting second-hand perinatal and infant clothes. Moreover, ICT has shown itself as an essential driver of responsible consumption, in accordance with an ICT-based collaborative economy.