The development of credit risk assessment models is often considered within a classification context. Recent studies on the development of classification models have shown that a combination of methods often provides improved classification results compared to a single-method approach. Within this context, this study explores the combination of different classification methods in developing efficient models for credit risk assessment. A variety of methods are considered in the combination, including machine learning approaches and statistical techniques. The results illustrate that combined models can outperform individual models for credit risk analysis. The analysis also covers important issues such as the impact of using different parameters for the combined models, the effect of attribute selection, as well as the effects of combining strong or weak models.Credit risk arises when a debtor (firm or individual) cannot fulfill its debt obligations towards the creditors. Credit risk assessment is performed through the development of models that are used to estimate the probability of default for a given debtor over a specific time period (usually one year). Such models are used for credit approval and monitoring and are of major importance, mainly for banking institutions. Commercial and industrial firms may also use such models to assess the credit quality of their clients.The development of credit risk assessment models is usually based on a classification approach, in order to distinguish potential defaulters from non-defaulters. Generally, classification refers to the assignment of a finite set of objects into predefined classes. Other well-known problems in finance that fall within this context include, among others, bond rating, country risk assessment, stock evaluation, and corporate mergers/acquisitions (Altman et al., 1981;.