This paper investigates the role of instructional supervision in teachers' delivery of the curriculum in four selected primary schools in Chipata District, Eastern Province, Zambia. The study was guided by three specific objectives: to analyse the influence of instructional supervisory approaches on curriculum delivery, to examine teachers' perceptions towards instructional supervision, and to develop strategies for strengthening the supervisory function in primary schools. Anchored within the theoretical traditions of Human Relations Management — specifically Argyris's Human Resources atmosphere model and McGregor's Theory Y — the study employed a convergent mixed-methods design, integrating quantitative data collected through structured Likert-scale questionnaires administered to 19 teachers and 4 head teachers with qualitative data gathered through a semi-structured interview with the District Education Standards Officer (DESO) and focused group discussions with 32 upper-primary pupils. Document analysis of eight teachers' instructional files provided additional triangulating evidence. Findings revealed that instructional supervision exercised a significant and predominantly positive influence on teachers' preparation of pedagogical documents, lesson delivery effectiveness, use of teaching and learning aids, and teacher-pupil contact time. However, the study also identified a pronounced gap between policy mandates and supervisory practice: only 14% of district teachers were supervised by Education Standards Officers in the preceding year, and fewer than half were internally monitored the requisite three times per term. Teacher perceptions were divided, with 42.6% holding negative views characterising supervision as fault-finding, inspection-oriented, and insufficiently collaborative. The study recommends sustained capacity building for head teachers in collaborative supervisory approaches, provision of adequate instructional resources, reduction of administrative overload on school leaders, and institutionalisation of regular, structured feedback mechanisms.