The objective of this thesis is to determine whether it is possible to improve the adequacy of support to “post start-up” small businesses in Sri Lanka by making changes to the current support regime to encourage their growth. The interest in this issue stems from (a) previous research carried out which highlights the substantially lower contribution to employment growth from the small businesses in Sri Lanka as compared to what is observed in other countries, and (b) the increasing emphasis upon stimulating the small business sector to make a significant contribution to the national economy which is apparent in recent policy proposals in the White Paper presented by the Task Force for Small and Medium Enterprise (SME) development. An examination of extant literature suggests that the understanding of the factors that influence the growth of post start-up small businesses in developing countries is limited. Knowledge is also limited on the type of support that is required to adequately address such factors. To systematically investigate the existing knowledge gaps in these areas a questionnaire survey was conducted. In-depth interviews were also carried out with small business owner-managers and key employees of organisations providing small business support. A variety of statistical techniques were employed to analyse the responses to the questionnaire survey. Overall the results indicate that the factors influencing the growth of post start-up small businesses are highly individual in nature. Results of the study also indicate that the employment growth in post start-up small businesses is very limited. Drawing on the results of the research a conceptual model is proposed that suggests a holistic approach to the identification, evaluation and delivery of support to address the factors constraining the growth of post start-up small businesses.