Three important infant feeding support problems are addressed: (1) mothers who use formula milk can feel undersupported and judged; (2) mothers can feel underprepared for problems with breastfeeding; and (3) many mothers who might benefit from breastfeeding support do not access help. Theory of constraints (TOC) is used to examine these problems in relation to ante-natal education and post-natal support. TOC suggests that long-standing unresolved problems or ‘undesirable effects’ in any system (in this case a system to provide education and support) are caused by conflicts, or dilemmas, within the system, which might not be explicitly acknowledged. Potential solutions are missed by failure to question assumptions which, when interrogated, often turn out to be invalid. Three core dilemmas relating to the three problems are identified, articulated and explored using TOC methodology. These are whether to: (1) promote feeding choice or to promote breastfeeding; (2) present breastfeeding positively, as straightforward and rewarding, or focus on preparing mothers for problems; and (3) offer support proactively or ensure that mothers themselves initiate requests for support. Assumptions are identified and interrogated, leading to clarified priorities for action relating to each problem. These are (1) shift the focus from initial decision-making towards support for mothers throughout their feeding journeys, enabling and protecting decisions to breastfeed as one aspect of ongoing support; (2) to promote the concept of an early-weeks investment and adjustment period during which breastfeeding is established; and (3) to develop more proactive mother-centred models of support for all forms of infant feeding.