Food waste is considered to be a big problem worldwide. Different research projects have been done within this area in order to find ways that can help reduce this problem. This thesis addresses the problem of food waste in the supermarkets of Kosovo, by identifying the amounts of food waste in 3 supermarkets of this region. In addition, it explores the possibility of connection between supermarkets and charity organizations by using a developed prototype that corresponds to the field of web technologies. The prototype is implemented based on the feedback of supermarket workers. Interviews with open-ended questions were realized with supermarket workers and charity organization workers in order to identify the best medium that can be used to connect them. The prototype is realized using Wordpress, and evaluated first using the SUS questionnaire. Furthermore, it is also evaluated by performing usability test with supermarket and charity organization workers. The participants were asked to perform different tasks during the evaluation. The study shows that the use of the developed prototype reduces the amount of food waste in supermarkets. Furthermore, it successfully connects charity organizations with supermarkets. In addition, it provides a new way of controlling expiry dates of items resulting in reduction of waste inside supermarkets.

La présence de personnes sans-abri dans l’espace public est un problème social ancien auquel depuis longtemps l’État cherche à remédier. À partir des années 1990, et plus encore après la promulgation, en juillet 1998, de la loi de lutte contre les exclusions, l’action publique s’incarne dans des dispositifs dits de « veille sociale » dont la mise en œuvre est majoritairement confiée, par délégation de service, au monde associatif. Parmi ces dispositifs, les « maraudes » désignent l’action d’équipes mobiles dont la mission est d’aller à la rencontre des sans-abri directement dans la rue. Les maraudes constituent l’objet empirique de cette thèse dont l’objectif est d’étudier cette activité en tenant compte à la fois de la pluralité de ses opérateurs – particulièrement des associations – et de la diversité de ses intervenants salariés et bénévoles, professionnels (notamment du travail social) ou non-professionnels. À partir d’une enquête ethnographique menée à Paris dans trois associations de solidarité et combinant observation participante et entretiens biographiques, l’enjeu est d’éclairer les tensions inhérentes à cette situation de coprésence d’acteurs collectifs et individuels en analysant conjointement les maraudes comme un monde du travail et comme un espace d’engagement. Par ces entrées analytiques, il s’agit plus généralement de contribuer à la compréhension des dynamiques de frontières dans un secteur – celui de l’urgence sociale – où persistent des ambiguïtés entre travail social et bénévolat, entre action publique et secours privé, entre valorisation de la professionnalité et reconnaissance du dévouement altruiste, et dans lequel les limites entre les missions sont incertaines. Une perspective interactionniste, inspirée à la fois de la sociologie du travail et des professions, permet en premier lieu de soulever le rôle central des pouvoirs publics dans la régulation de l’activité par la diffusion de multiples injonctions – notamment à la « professionnalisation » et à la « coordination des maraudes » – auxquelles les trois organisations enquêtées souscrivent différemment, allant d’un rapport d’alliance à un rapport d’autonomie. L’étude de la division du travail éclaire ensuite la hiérarchie de noblesse des tâches ainsi que leur distribution, qui valorisent les fonctions d’accompagnement social prioritairement attribuée aux « maraudes professionnelles » et déprécie les missions de distribution, notamment alimentaire, qui incombent aux « maraudes bénévoles ». L’observation de stratégies de résistance à cette division – les équipes bénévoles souhaitant également assurer le « suivi » des sans-domicile – révèle dès lors l’existence de luttes de juridiction qui ont pour enjeux le contrôle d’un territoire à la fois spatial et professionnel mais aussi la maîtrise des savoirs essentiellement tacites et acquis par l’expérience. Empruntant à la sociologie de l’engagement, un regard resserré sur les maraudeurs et leurs trajectoires autorise en second lieu le dépassement de cette opposition (professionnel/bénévole). D’abord en montrant l’intrication et l’hybridation des carrières bénévoles et professionnelles, les maraudeurs salariés ayant très souvent eu une pratique de bénévolat préalable et certains bénévoles utilisant la maraude comme une expérience de préprofessionnalisation dans le travail social. Ensuite, en identifiant des continuités dans les façons de voir et d’exercer l’activité qui transcendent les appartenances associatives et les conditions statutaires pour mieux révéler l’influence de modes de socialisation (familial, militant, professionnel). / The presence of homeless people in the public space is an ancient social problem that the State has been attempting to solve for a long time. From the 90’s on - and especially after the enactment, in 1998, of the law fighting against social exclusion - government intervention has been embodied in a package of social measures under the umbrella term of “social watch” (“veille sociale”). Its implementation has been mainly entrusted to not-for-profit associations and charities, through delegation of public service programs. Among these measures, the mobile outreach programs describe the action of mobile teams given the mission to connect and engage with homeless people in the streets. The mobile outreach program constitutes the empirical subject of this thesis. The aim is to study this activity by taking into account the plurality of its actors - especially the not-for-profit associations - and the diversity of its contributors, both employees and volunteers as well as professional and non-professional social workers. Based on an ethnographic study led in Paris involving three different charity organizations, it combines participant observation and biographical interviews. The aim is to bring into view and clarify situations of inherent tension in this copresence of collective and individual actors through an analysis of mobile outreach programs as both places of work and social commitment. This analysis more generally enables an understanding of the dynamic boundaries within the field of social urgency, in which there are many persistant ambiguities. Ambiguities abound between social work and volunteering, public actions and private initiatives, between the prominence given to promote professionalism and the acknowledgment of altruistic dedication. The boundaries among these different missions remain vague and uncertain. An interactionist perspective inspired by the sociology of work and employment enables us to raise the issue of the main role played by the public authorities. They regulate the social outreach activity through multiple injunctions, notably with particular emphasis on professionalization and coordination of the mobile outreach program. The three different organizations that are the subject of enquiry take different approaches to those injunctions, whether in a relation of alliance or autonomy. The analysis of work divisions sheds light on the hierarchical division of labour as well as the question of how tasks are delegated. Social support and follow up missions are prioritised to professional outreach workers while responsibility for the less well considered missions such as food runs and distribution are handed over to the volunteer outreach workers. Observation of the different strategies of resistance towards this division reveal a struggle over jurisdiction – volunteer outreach workers equally want to be a part of the support and follow up missions and highlight what is at stake: the control of territory both physical and professional, as well as the mastery of knowledge which is essentially tacit and acquired through experience. By looking closer at volunteer outreach workers and their trajectories through the lens of sociology, the boundary between professional and volunteer can be seen to be an artificial one. First, by showing the overlap and hybridisation between the trajectories of volunteers and professionals: wage-earning outreach workers have a lot of the time practiced volunteering before, while on the other hand, some volunteers use the outreach programs as a way to enter the professional world of social work. Then by underlining the continuity in the way of seeing and practicing the activity that transcends organizations’ affiliations and status to better reveal the influence of different modes of socialization, be it through family, advocacy or work.