The documented dataset covers Enterprise Survey (ES) panel data collected in Tanzania in 2006 and 2013 as part of Africa Enterprise Surveys rollout, an initiative of the World Bank. New Enterprise Surveys target a sample consisting of longitudinal (panel) observations and new cross-sectional data. Panel firms are prioritized in the sample selection, comprising up to 50% of the sample in the current wave. For all panel firms, regardless of the sample, current eligibility or operating status is determined and included in panel datasets. Tanzania ES 2013 was conducted between January 2013 and February 2014, and Tanzania ES 2006 between November and December 2006. The objective of Enterprise Surveys is to obtain feedback from enterprises on the state of the private sector as well as to help in building a panel of enterprise data that will make it possible to track changes in the business environment over time, thus allowing, for example, impact assessments of reforms. Through interviews with firms in the manufacturing and services sectors, the survey assesses the constraints to private sector growth and creates statistically significant business environment indicators that are comparable across countries. Data from 1,142 establishments was analyzed: 698 businesses were from 2013 ES only, 394 from 2006 ES only, and 50 firms were from both 2006 and 2013 panels. Stratified random sampling was used to select the surveyed businesses. The data was collected using face-to-face interviews. The standard Enterprise Survey topics include firm characteristics, gender participation, access to finance, annual sales, costs of inputs and labor, workforce composition, bribery, licensing, infrastructure, trade, crime, competition, capacity utilization, land and permits, taxation, informality, business-government relations, innovation and technology, and performance measures. Over 90 percent of the questions objectively ascertain characteristics of a country’s business environment. The remaining questions assess the survey respondents’ opinions on what are the obstacles to firm growth and performance.