Submitted in fulfilment of the requirements for the degree of Masters of Arts in the Department of Geography at University of Zululand, South Africa, 2000. / There has recently been an increase of clusters of informal business operators in different parts of the city of Pietermaritzburg. Allegations have been made that street vending causes pollution of the environment in the city and that it was an illegal activity associated with crime and other anti-social activities that were inimical to formal business enterprises and the viability and sustainability of the city of Pietermaritzburg. This dissertation was conducted in the context of Agenda 21 of the Rio Earth Summit which advocates for sustainable development of business enterprises, which governments worldwide were persuaded to adopt in their development planning policies. The Pietermaritzburg-Msunduzi Transitional Local Council (TLC) has recently initiated a move to implement the Local Agenda 21 programme as advocated by the Rio Declaration. The main aim of the dissertation was to examine the impact of the informal business enterprises on formal business and the environment, and thereby determine the sustainability of the city of Pietermaritzburg. It was found in this dissertation that street vending was related to the high rate of unemployment in Pietermaritzburg, and that both males and females in their productive years were involved in street vending. Informal businesses were found to be partially responsible for littering and environmental pollution in the city by generating litter from the items they sold on the streets. It was also found that many of the street vendors lived in squalid informal settlements or on the street pavements which contributed to the pollution of the city's environment. It was found that their actions resulted" from an involuntary and necessary condition of poverty. The Street vendors were actually actively engaged in cleaning up operations and environment education in accordance with local Agenda 21. The informal business enterprises were found to be recognised legal activities that cooperated with formal business, the city council and other stakeholders in the fight against environment pollution and crime. It was found that there was a complementary relationship between formal and informal business, which did not jeopardise formal commerce and industry and the sustainability of the city of Pietermaritzburg. It is argued in this dissertation that, with more positive encouragement and assistance, the informal sector is an essential means of alleviating the problems of unemployment and poverty. Guided in the correct direction, the informal business enterprises are a way of promoting the viability, development and sustainability of the city of Pietermaritzburg.