Several efforts have been made through research, government programs and Non-Governmental Organisations (NGO) interventions to improve yam production in Nigeria. In addition, some policies targeted at improving agricultural production have weakened the production and consumption of different commodities, especially yam. This study analyzed the effects of policy changes on yam production and consumption in Nigeria. A multi-stage sampling technique was used to select 700 respondents for the study. Primary data was collected using pre-tested structured questionnaire while interview guide was used to collect information in a Focus Group Discussion. Data were analyzed using Multi-Market Model. The results showed that that policy changes on yam substitutes, particularly rice, sometimes have negative effects on yam production, prices, land share and real income among yam farming households in Nigeria depending on the nature of the policy. [EconLit citations: C3; C6; D1]. C 2015 Wiley Periodicals, Inc. According to Lipsey (1999), government interventions are usually through policy formulation for changes. These policies could be fiscal, monetary, agricultural or through initiating a program with the aim of improving welfare in the rural and urban areas. In the agricultural . My research focus is on agribusiness, competitiveness of agricultural products, economic transformation through small scale agriculture, financing, gender issues, partial equilibrium models, and welfare maximization among farming households in Nigeria. Algiers, Algeria. He specialized in quantitative economic analysis and worked on benefit cost analysis, partial equilibrium modeling (Economic surplus models) and General Equilibrium models in Cameroon. He taught these models to more than 600 scientists (economists and noneconomists), extension, NGOs, project managers. Now more of his work is training country research and private sector in developing innovation platforms and efficient value chains. Robert Asiedu is