Background: This article investigates emotional intelligence and locus of control in an adult breast cancer population receiving treatment. Gaining insight into these constructs will contribute to improving breast cancer patients' psychological well-being and to reducing physical vulnerability to disease before and during treatment.

Method: The researcher used an exploratory, descriptive and correlational approach. Nonprobability purposive sampling was employed. Sixty-seven breast cancer patients receiving treatment participated in the research. A biographical questionnaire, the Schutte Emotional Intelligence Scale, and the Rotter Internal-External Locus of Control Scale were used to measure the constructs explored in this article. Descriptive and inferential statistics were used to analyse the data.

Results: The sample yielded above-average levels of emotional intelligence and an internal locus of control. The results indicate a statistically and practically significant negative correlation between emotional intelligence and locus of control. The significant association found between higher and lower emotional intelligence groups and internal and external locus of control groups also confirmed these results.

Conclusion: Having an understanding of the psychosocial variables that impact on individuals diagnosed with a chronic illness, in this case breast cancer, can assist interventionists working in the field of positive psychology. While the stressors and challenges that breast cancer patients face are well documented, this article highlights the strength factors emotional intelligence and locus of control as important mediators in the treatment and management of breast cancer.