Type 2 Diabetes Mellitus (Type 2 DM) is present in the populations of almost all the countries in the world and is a significant disease burden in most developed countries. Evidence suggests that populations in Africa develop Type 2 DM at an increasing rate as they reject their traditional lifestyles. Furthermore, newly released figures by the Medical Research Council of South Africa indicate that diabetes is the 10th most common cause for total life years lost in females in South Africa. Exercise is a low cost, non-pharmacological intervention that has been shown to be effective in metabolic control. Exercise is still vastly under-utilised in the management of Type 2 DM, especially in urban black females with Type 2 DM. This study was designed to determine the effectiveness of an exercise intervention to decrease haemoglobin A1c (HbA1c) over period of 12 weeks in Type 2 DM black female subjects, aged 40to 65 years. This study consisted of three phases. Data captured in the first two phases were utilised to plan the exercise intervention. Questionnaires and focus groups were used in the first two phases of the stud. The final phase of the study consisted of a randomized controlled trial. For this phase 157 female subjects who were recruited at the Mamelodi hospital diabetes outpatient clinic, were randomized to either an experimental or a control group. It was found that the subjects had little knowledge about their disease and that they lead a sedentary lifestyle. Subjects felt that Type 2 DM had a negative impact on their lives. Their attitudes bout Type 2 DM showed a dependence on health professionals and they disagreed with the attitude that they should be involved in decision-making about their health care. The results of the focus groups indicated that patients viewed walking and household chores as suitable exercise for them. Personal barriers to exercise were lack of knowledge, tiredness and health-related stress. Subjects expected that exercise would increase the functional capabilities, increase their knowledge and improve their well being. These findings were used to plan the exercise intervention, which consisted of a home-based exercise programme and fortnightly exercise sessions at the Mamelodi hospital. Subjects also had to complete a diary of their physical activities at home. An analysis of co-variance (ANCOVA) was used to compare the experimental and control groups with respect to change in HbA1c and the secondary outcomes such as walking distance and quality of life outcomes. It was found that the exercise intervention was no more efficacious (p=0.05) than a supervised self-relaxation training intervention to decrease HbA1c, over a period of 12 weeks. The exercise group was however able to walk a significantly further distance (p<0.01) than the control group after the 12-week intervention. While not significantly different between groups (p=0.80), the positive well-being improved significantly within both groups (p<0.01). It is possible to improve blood glucose control by means other than medication in urban black female patients with Type 2 DM. The patients are willing to change their sedentary lifestyle to a more active one, but several environmental and personal barriers impact negatively o their attempts to do so. The role of the health care worker is to identify these barriers and to accompany the patient on the road to a healthier lifestyle. However, this population of women may need more assistance and support initially to take self-responsibility for their diabetes self-management eventually.