Entrepreneurship is the manifestation of human ability that has absorbed Business Administration scholars due to its economic importance and its social impact. Brazil has stood out as one of the countries with the highest level of Entrepreneurship in the world, and the perception that the development of entrepreneurial activities can be one of the decisive factors in a country´s economic development grows at an ever-increasing rate. Scholars in other countries suggest that the initial and principal point in the Entrepreneurship process is the activity of constantly and creatively seeking new business opportunities. This study reviews works on Entrepreneurship in Brazil, published through the various means classified to be the most representative of the Business Administration research conducted in the country. This study aims to achieve a better understanding of how entrepreneurs who have achieved success in their ventures identify and handle new business opportunities. To accomplish this, the sources of opportunities available had to be identified and categorized. Therefore, in the review of Entrepreneurship theory, 2 models relating to this topic were proposed, one referring to the sources of new business opportunities, and the other referring to the process of identifying opportunities and creating new businesses. The study was based on the application of a questionnaire, followed by interviews with entrepreneurs in Brazil. The results indicate that there is a large concentration of new ventures that derived from opportunities detected inside the companies and others that originated from research, as well as ventures that stemmed from the entrepreneur´s inspiration.