Zambia’s transportation policy highlights gaps in the transportation sector. This review focuses on analysing railway freight services and provides a departure from other similar reviews through a critical review of the Zambia railway sector gaps. The study sought to review existing literature, reports, and online information sources on Zambia railway freight services by grouping challenges into thematic groups. Causal loop analysis is used to identify cause and effect relationships among challenges specific to Zambia. Findings indicate that Zambia’s railroad infrastructure quality score (2.4) benchmarks below the average mean score (3.5) of all countries in 2017 and further benchmarks below the income group ‘eight-year average’ mean scores on infrastructure quality and train efficiency. Zambia has been recording declining railway volumes in terms of ton-km over a 37-years period. Five main thematic areas are identified as the main challenges for the railway sector in Zambia. These include infrastructure/ equipment gaps, quality gaps, human resource gaps, investment gaps, policy/political will/regional coordination gaps, and business viability gaps. The study recommends the need to improve investments in the railway sector and strengthen government commitment to resolve the majority of challenges currently associated with Zambia’s railway sector.