Magister Curationis - MCur / Background: Motivational interviewing is an approach that relates to a person’s hopes and aspirations. It is individual-focused to enhance intrinsic motivation to change. Over a decade, motivational interviewing has been shown to help achieve positive client outcome regarding substance use at various health settings in high income countries. In the Western Cape, clinical evidence suggests there is increase in number of children born with abnormalities related to prenatal exposure to substance. Anecdotal evidence suggests that the current support system in place for women who have children that are suffering from the effect of prenatal substance exposure seems not to be helping. As agents of change some NGOs in Western Cape are working towards decreasing substance use among pregnant women. Problem statement: The NGOs involve groups of individuals in Cape Town who render their service voluntarily to help pregnant women who have problem of substance use. They help motivate and support pregnant women to live a healthy lifestyle. It is however uncertain if personnel in these NGOs have knowledge of motivational interviewing. Aim: In the absence of the above information, this study is therefore aimed to explore NGO personnel’s knowledge on the use of motivational interviewing in addressing substance use among pregnant women in Western Cape. Method: A quantitative approach using a descriptive design with a non-probability all-inclusive sampling was used. A total of 45 participants were drawn from NGO shelters and day centres working with pregnant women who use substance in the Southern sub-urban district of Cape Town metropolis. Structured questionnaires were given to the participants for data collection and the response rate was 53% (n=24). Data was analysed using descriptive statistics. Results: The results of the study showed that the general performance of the participants on knowledge of motivational interviewing was poor. The score of most participants (i.e. mode) fell within 31 – 40%. Hence, the distribution of the scores was skewed toward the failed side. The percentages of males and females that passed were very low and the values were very close. Hence, gender was found not to influence the performance of the participants in this study. Lack of training in motivational interviewing was found to be responsible for lack of knowledge of the concept. There was no correlation between years of experience and age of participants on performance in the evaluation. The knowledge of participants on characteristics of substance user and the dynamic client-therapist’s interaction was very shallow. Participants who agreed to myths regarding substance users were most likely to exhibit actions that were not consistent with principles of motivational interviewing during their interactions with clients. The participants did not have adequate knowledge of the five basic principles of motivational interviewing. The conclusion of the study was that there was need to train NGO personnel in the concepts of motivational interviewing.