Information quality has become a critical concern to the success of organisations. Numerous business initiatives have been delayed or even cancelled, citing poor-quality information as the main reason. Previous research indicated that under-standing the effects of information quality is critical to the success of organisations. However, little research has been done to analyse the effects of information quality in an organisational context. In order to address this drawback, the objective of this thesis is to systematically analyse the effects of information quality on decision-making. In order to achieve this objective, we propose a practical assessment framework that allows us to measure information quality dimensions and categories. This framework was validated using a real-world database. With the help of this assessment framework we gained in-depth insights into the effects of information quality on decision quality. Our results showed that the categories of intrinsic and contextual information quality are positively related to decision quality. However decision quality is not significantly affected by representational information quality. It is also found that in contrast to consistency, increasing information accuracy and completeness can significantly improve decision quality. From our results we concluded that not all the aspects of information quality are equally effective for the improvement of decision quality. Decision-makers could decide to pay little or no attention to the improvement of representational information quality and information consistency. This finding will directly reduce the cost of information quality improvement. For practical implementations, our results concluded a validated framework that allows software engineers to implement assessment. Comparing our framework with other common frameworks that require soft-ware engineers to understand information quality theory, our framework helps soft-ware engineers to follow a step-by-step procedure to build an application of information quality assessment. It will directly increase software engineers' work efficiency.