Multiple Sclerosis (MS) patients are faced with complex risk-benefit profiles of disease-modifying drugs (DMDs). It is important that MS patients are able to understand the risks and benefits of DMDs in order to make an informed treatment decision. The goal of the present thesis was to identify the best methods of presenting treatment risks and benefits to improve MS patients' understanding and reduce conflict in their treatment decisions. First, systematic reviews and surveys were conducted to inform the need to improve MS patients' understanding of treatments. Subsequently, three experiments were designed to assess the effect of different presentation methods on MS patients' understanding of hypothetical treatments. Experiment 1 found that treatments presented using non-graphical formats had an effect on patients' understanding (p < .001), with numerical frequencies improving understanding the greatest. Understanding of treatments was also affected by presentation using graphical formats (p < .001), and was greatest for bar charts and line graphs. Experiment 2 found that presenting treatments using ratios (p < .001) and frames (p < .05) also affected patients' understanding. Experiment 3 showed that the methods to communicate differences in the risks and benefits of clinical trial groups further had an effect on patients' understanding of treatments (p < .001). The BRIMMS protocol was developed by integrating the best presentation methods from Experiments 1-3 and was compared with standard consultation using a randomised controlled trial with crossover design. The BRIMMS protocol improved understanding (p < .001) and reduced decisional conflict (p < .001) in comparison to standard consultations. In conclusion, some methods to present treatments can improve MS patients' understanding of treatment risks and benefits. The BRIMMS protocol could potentially be implemented into current clinical practice to improve MS patients' understanding and engagement in the decision-making process.