<p>  </p> <p>Food systems are facing unprecedented challenges and need reforms to be more efficient and provide safe and nutritious food from farm to fork. In this dissertation, I present new empirical evidence on different strategies to tackle two critical problems of food systems in sub-Saharan Africa (SSA): food contamination and the inefficient delivery and use of subsidized agricultural inputs. The first essay measures demand and network effects for a newly available technology called Aflasafe that delivers credence attributes (i.e., benefits difficult or impossible to observe and measure even after frequent use of the technology). The second essay exploits a policy change in Malawi to estimate the efficiency of public and private channels at distributing inputs to smallholder farmers. I use a panel dataset covering the period from 2010 to 2016 and a difference-in-differences (DID) framework to estimate the impact of the policy change on procurement of subsidized fertilizer, efficiency and service quality, agricultural productivity, and the household’s decision to purchase commercial fertilizer. The third essay identifies a series of constraints faced by smallholder farmers in Senegal and assesses which ones are associated with chemical and microbial contaminants in groundnut (peanut).</p>