Internationalization is a broad research field with an extensive variation of sub-fields and a widely ramified network of terms and definitions. The internationalization patterns are one sub-field of interest, describing various ways how SMEs are implementing internationalization nowadays. The incorporation of the recent research streams internationalization stages and internationalization dimensions brings further light into the internationalization process of SMEs. Within the internationalization process, the market assessment provides the basis for international market selection decisions. Despite the prevalence of international market selection models, little is known about the influence of internal and external factors on the international market selection decisions and the market assessment. The concurring opinion of researchers (Simon, 2007, Brouthers et al., 2009; Rahman, 2013) is that current international market selection models insufficiently describe the internal and external environment and lack the incorporation of the internal environment into the market assessment. Especially, the description of the internal environment in the context of internationalization suffers from the use of superordinate categories and terms, instead of illuminating underlying factors. The aim of this thesis is, therefore, to determine the internal and external factors for the market assessment of SMEs, and pinpoint strategic factors with increased influence on the international market selection decisions. Next to revealing highly influential macro-, and meso-level factors, such as, the size of the high-class segment, the buying power, the consumption behaviour, the norms and regulations, the complementary products/industry and the low-cost industry for the market assessment of SMEs; the findings also revealed an extensive number of internal factors with high influence on market assessment and international market selection decisions (IMSDs). The high-influential internal factors revealed are: gut-feeling of the management, weighting of investments, the commitment of partners in the foreign markets, the resources of those partners, and the distribution experience of those partners, the geographic distance, Psychic Distance, language, the international heritage of the SME, and product-specific rules and regulations, market-specific budget, and the capacities of the management. Suggesting that market-specific costs, the capacities and qualification of the management, the language proficiency and the availability of local partners in the foreign market are strategic factors, this thesis provides a recommendation for SMEs to adapt their market assessment process and incorporate those contributing internal factors into IMSDs.