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The 4‰ initiative launched by the French government at COP21 in Paris in December 2015 aspires to increase global soil organic carbon (SOC) stocks at a rate of 0.4% per year. We conducted a systematic literature review on SOC storage under agroforestry and conservation agriculture systems in sub-Saharan Africa, where we reported 66 and 33 cases for both systems respectively. The results showed that SOC storage rates were significantly higher than 4‰ yr⁻¹ in fallows and in multistrata agroforestry systems (P = 0.0001 and 0.0178, respectively), but not in alley cropping and parklands systems. For conservation agriculture, SOC storage rates were only significantly higher than 4‰ yr⁻¹ (P = 0.0438) when all three principles were applied, i.e. no- or minimum tillage combined with crop residue retention and intercropping or rotation. The data showed very large variability in SOC storage rates as the result …