In some settings, steps are being taken to more fully integrate pharmacists in primary health care as a means of improving the public’s health and reducing drug-related iatrogenesis. Yet, evidence of improvement in health outcomes from pharmacists’ inputs is mixed; the diversity of research approaches and methodologies makes it difficult to reach an overall conclusion about it. A detailed review and analysis of two published articles using different methodological approaches to assess the role of community pharmacists in primary health care, but similarly reporting unfavourable findings regarding pharmacists’ impacts, is conducted. The Randomized Controlled Trials (RCT) design did not account for possible within-group differences in the delivery of the pharmacist intervention, and could not ascertain there were differences in pharmaceutical care received by intervention and control group heart failure patients. The RCT did not include an evaluation of pharmacists’ recommendations to physicians. The qualitative discourse analysis did not distinguish between patients’ response to pharmacists’ recommendations and the appropriateness of those recommendations. Researchers face two key challenges in demonstrating pharmacist impacts in primary care. The first is methodological – and relates to the need to identify, measure and evaluate the range and complexity of pharmacists’ work in conducting medication review and pharmaceutical care. The second relates to the differing levels of status and power of two key players in the field of medicines-related health care – the physician and pharmacist – a relationship whose contribution to "negative impact" studies needs consideration. An appeal for "methodological creativity" in pharmacist impact studies is made.