The use of monitoring devices (data collection) in business organizations is facilitated through New Information and Communication Technologies (NICT) such as fingerprint, facial or eyes biometric, time clocks, cyber surveillance, remote tracking of employees via GPS, and others. While standard economic theory advocates the use of incentive systems and surveillance to increase performance at work, some empirical studies show a fall in the level and quality of effort after the introduction of monitoring. Using self-determination theory (SDT), we explain this phenomenon by the negative impact of “monitoring systems extensiveness” on employees’ intrinsic motivation (IM). We hypothesize the mediation of this impact by the degree to which employees perceive their supervisors as being “autonomy supportive”. We also investigate the possibility of a moderating effect of “employees’ beliefs about the purposes of devices for monitoring” on the relationships between “monitoring systems extensiveness”, “perception of supervision” and “intrinsic motivation”. We test these hypotheses using a questionnaire, collected in France, from 579 employees having at least one supervisor. Developing a structural equation model, we find: firstly, a significant crowding out effect of IM by monitoring; secondly, this crowding out effect is significantly mediated by employees’ perception of supervision; thirdly, we confirm a strong positive relation between an autonomy supportive supervision and IM. Finally, we do not find any significant moderation by employees’ beliefs about the purposes attributed to monitoring devices.