Unwelcome behavior is within the Swedish Armed Forces unacceptable and is to be prevented. Sweden has received new tasks that involve not only the defense of Swedish territory but also that of allied nations against armed attacks. Therefore, more officers are needed to meet the new demands, threats and tasks. Motivation is a key factor in retaining personnel, especially now during a time of organizational growth. This thesis examines through a quantitative survey, how unwelcome behavior affects the motivation to work within the Armed Forces among cadets in their first, second and third year of the officer´s program at the Karlberg Military Academy. The result is analyzed using the Self-determination theory and shows that cadets who have observed or been subjected to unwelcome behavior, regardless of type or context, experience a negative impact on their motivation to study at Karlberg and to work within the Armed Forces. However, the degree to which motivation is affected varies depending on who is subjected, by whom and in what situation. Female cadets are slightly overrepresented in the survey and are more often than male cadets subjected to unwelcome behavior, especially sexual harassment. However, more men than women report being subjected to discriminatory treatment. Unwelcome behavior that occurs during or outside of school hours on the Karlberg campus, especially sexual harassment, has the most negative impact on the motivation.