According to service dominant logic (SDL), customers are always active participants and collaborative partners in exchanges; therefore we should focus on the elements of consumer behaviour that are connected with the value co-creation. By involving the customers in service production, providers can capture customers' needs and maintain their competitiveness. The cutomers' roles may lead to a higher productivity and competitive quality for companies. Previous researches recognized two types of the customers' co-creation behaviour. First, it is the consumers' participation behaviour. Then, the other one is the consumers' citizenship behaviour. The goal of our study is to examine how the level of involvement influences two kinds of behaviour mentioned. Besides, we explore if respondents' participation behaviour or citizenship behaviour influence the perceived value of service provided. In 2015, for examination of our research questions, we carried out a quantitative research and applied quota sampling to obtain data from two target groups (X and Y generations). The activity and attitude of individuals related to performance of an extra-role in service interaction is less favourable than the required in-role behaviour. According to the results of our survey, the level of involvement influences the customers' mandatory behaviour and volunteer behaviour when working on a co-creation value. Empirically verifiable, the service users' activity in a value creation affects customers' value of the service.