The traditional work relationship performed on a full-time basis with a single employer is tending to lose its hegemony. Polivka and Nardone (1989) defined these new work arrangements as contingent in opposition to permanent work positions. According to these researchers, contingent work includes “any job in which an individual does not have an explicit or implicit contract for long-term employment and one in which the minimum hours can vary in a non-systematic way” (1989: 11). Traditionally, contingent work includes part-time work, temporary work, “in-house” temporary arrangements and independent work. Today, these forms of employment represent a significant and growing proportion of the workforce in western countries.This research is dedicated to “in-house” temporary workers in the French context. Indeed, little research has dealt with this subject (Connely and Gallagher, 2004). The behaviours of this type of workers are quite unknown. Moreover, Conway and Briner (2002) point out that research which focuses on contingent work does not often use an explicit theoretical framework which may be helpful in understanding the organizational behaviours of contingent workers. In line with their recommendations, this study aims to identify the role of organizational justice on contingent workers’ organizational commitment and to show if established relationships are similar according to employment status (i.e., contingent or permanent).On the one hand, organizational justice perceptions have significant effects on several attitudes and behaviours (Colquitt, 2001) but this effect has rarely been tested on contingent workers. On the other hand, the employment status is likely to have an influence upon the relationships between organizational justice and organizational attitudes and behaviours. Moreover, according to the fairness heuristic theory (Lind, 2001) which describes the shaping of justice judgments and their use, it seems that a fixed-term relationship with the organization may lead contingent workers to focus primarily on the interactional aspects of their organizational treatment.This research is based on an empirical study carried out with a sample of 181 permanent employees and 71 contingent employees in French private clinics. The moderator effect of work status was tested with hierarchical regression analysis. The results partially support the predictions. However, they show the significant effects of justice perceptions on commitment, in the case of permanent workers, as had been already demonstrated in previous research, but also in the case of contingent workers, which has been less shown, especially for “in-house” temporary workers and in the French context. Nevertheless, the results show a moderator effect for work status on the relationship between informational justice and commitment.Several observations are drawn from these results. First of all, the results demonstrate that contingent workers are sensitive to the treatment they experience within their organization and that it influences their commitment as well as is the case for permanent workers. Therefore, organizational commitment of the permanent and contingent workers is significantly and positively influenced by their distributive, procedural and interactional justice perceptions. Secondly, the effects of informational justice are different according to job status. Indeed, the effect of informational justice is weaker in the case of contingent workers than in the case of permanent workers.These results present theoretical and practical interest. Firstly, they support and extend the predictive power of organizational justice upon commitment, mainly established in the context of traditional work. Thus, the organizational justice framework seems to be useful for the analysis of a non standard employment relationship. Moreover, this kind of employment arrangement may not be seen as an economic one as long as contingent workers seem to value the social aspects of their relationships with their organization. Secondly, our results show that according to the type of employment relation, the effects of justice perceptions may be different, even if this difference is marginal. For this reason, organizations could have an interest in implementing differentiated management of their workforce according to work status. We believe that the nature of the detected moderator effect does not decrease the importance of informational justice perceptions. It rather underlines the inappropriateness of the information given to contingent workers. Trombetta and Rogers (1998) have put the emphasis on this information and its appropriateness upon the organizational commitment of nurses and nursing auxiliaries. Thus, it seems of great importance to make sure that the explanations and information delivered to contingent workers are accurate and relevant. We also believe that our results reinforce the role of the direct supervisor. Because the direct supervisor is in charge of the integration of contingent workers within the service or the team, these supervisors have a key role. It could be necessary to make them aware of this. Therefore, the organizations which use contingent work arrangements should implement a specific human resource management approach in order to reap the benefits of quantitative work flexibility.