Book excerpt: Population growth and the drop in the returns from the major cash crop (coffee) for small farmers are the main drivers that have influenced the farming systems and mobility of farmers in the Western Highlands of Cameroon. The main objective of the research that led to this book was to determine the interactions between farming systems and human mobility in this region of Cameroon. A comparative study was conducted through household and field surveys in three villages and conceptualized based on the systems approach. The different types of mobility were influenced by household social factors, the quest for high valued farm plots and hired labour. Urban-rural migration contributed to occupation diversification and social mobility. The sustainability factor was a function of land use intensity, intensity of off-farm inputs, the household adjustment factor and mobility of the household. The sacred groves were rich in plant diversity of varied ecological and economic importance. Nitrogen mining was common at all levels of the farming system. These determinants and types of mobility claims are pertinent to the research area; the sustainability results of the farming systems reflect the reality on the ground; the nutrient flux evaluated at the crop and farm levels constitute a valuable database for future research.