Periurban areas are dynamic spaces, especially in developing countries where cities and city population are rapidly growing. They are multifunctional spaces where different land uses coexist, leading to very mixed landscapes. Agriculture is one of these land uses. Periurban agriculture is defined as all kind of cultivation systems, including livestock raising that occurs in the periurban areas. It has always existed since the creation of cities and can be found everywhere, from African to North American, from Asian to European cities. But its characteristics are very different from one place to the other. It can occur at different scales (from garden to large plantations), encompasses different production types, can be oriented towards self-subsistence or commercialization. Periurban farmers' livelihood is also encompassing different activities, agriculture being one of those. Periurban agriculture is told by development experts to have an important potential for sustainable development, especially because of its positive impact on urban food security which is now on top of the development agenda. Indeed, providing an easy and secured access to food for urban people is becoming a challenge as most of the cities in the world are depending on remote areas for food supply. However, this positive perception of periurban agriculture has not always been shared by the majority. Indeed, until recently, it has been neglected both by urban planners and agronomists as a fringe topic not deserving attention. Experts' new positive perception may however not be shared by the farmers at the local level. Indeed, following the action theory, perceptions are influenced both by personal characteristics, but also by the general conditions of actions (political, economic, ecological features) and social norms and value systems, depending on the context. For an understanding of the potential and constraints of periurban agriculture, it is therefore informative and important to study both experts' and farmer's views, as well as the arguments determining these views. This is why a case study has been conducted to get an idea of local farmers' perceptions of agriculture in the periurban area of Kathmandu, Nepal. The choice of this region was motivated by the existence of a city waste composting project of the Swiss enterprise Sciences & Environment named BIOCOMP and the need of the project manager to get information on the local system and on local farmers strategies. In order to investigate the perception of local farmers in the field, semi-constructed interviews have been conducted among 39 farmers in 7 different zones located at less than 5 kilometers from the ring road delimiting Kathmandu City. These interviews aimed to get farmers' perceptions of their environment and its transformation, of the positive and negative aspects of their profession and activities and of the constraints / opportunities for periurban agriculture. The arguments motivating these perceptions were also collected. All data was grouped and analyzed according to the SWOT (Strengths, Weaknesses, Opportunities and Threats) framework. This was complemented by an analysis of the socioeconomic and cultural context of the Kathmandu valley through literature research as well as informative interviews with local experts. As a general result, the analysis of farmers' and experts' perceptions of strengths and weaknesses of periurban agriculture underlines the importance of periurban agriculture in the Kathmandu valley for the regional economy and the livelihood of local farmers, according to both local farmers and experts. Yet more specifically, the in-depth analysis also identifies the different arguments formulated by the experts and by the farmers. Hereby, the study helps concretizing a general view of experts and provides a more accurate picture of the reality. It also highlighted the importance of social factors like the independence and good conditions of work as well as food security for the local farmers. The analysis also allows the statement that a waste composting project helps alleviating a perceived constraint (the lack or low availability of fertilizer and the lack of time and workforce to produce it), and can therefore be a-priori evaluated as socially acceptable. However, lack of fertilizer was not the only constraint mentioned by the farmers. The study also highlights the multiplicity of constraint. Lack of integration in land use planning obtained the highest level of consensus between experts and farmers, followed by the water availability and quality. These two points therefore can be considered as major entry points for political action. As a conclusion, Periurban agriculture in the Kathmandu valley is an important element for the livelihood of people. Its role is acknowledged by both experts and local farmers and therefore deserves political support, based on suited entry points. A qualitative field study of general and local perceptions of periurban agriculture and its constraints in the Kathmandu valley provides a first insight and allows identifying these entry points that can serve policies and project designers.