Sierra Leone is a West African country that had brighter prospects after independence from The British in 1961. The expectation was that with the strong foundation laid by the colonial masters coupled with the abundant natural resources, the country's own indigenous "new crop of managers" will utilize this advantage to propel the country towards a strong path of growth and development. Almost 56 years after independence, the country is characterized by acute poverty, high inequality, illiteracy, low life expectancy, high unemployment especially among the youth, etc., because of gross mismanagement of our natural resources, rampant corruption and a catastrophic revel war. Hence, this work on "The Dark Side of Sierra Leone's Development in the 21st Century" seeks to identify and present the critical sectors of the country's development and advance recommendations to turn the situation around. Therefore, the "dark Side" has been defined as "areas or sectors in which significant improvements have not been made over time, making the benefits of development in the country unfelt by the majority of Sierra Leoneans".