The impact of structural adjustment programme on the economic situation in many African countries can not be overemphasised. Over more than a decade of implementing neo-liberal economic policies by the Bretton Woods institution it is of great importance to document the lessons learnt. This paper explains how the expected effect of structural adjustment policies produced unintended effects which cut back the gains of the programme. Using causal analyses, the assumptions and hypotheses implicit in the six main structural adjustment policies are clearly elicited with a causal loop diagram. The paper concludes, though structural adjustment programme was not a complete failure, the policies generally did not deliver the expected promises due to lack of systematic analyses and understanding of the policy responses by stakeholders.