Mycorrhizae formed between plant roots and zygomycetous fungi are ubiquitous and can improve the productivity of most crop plants. The use of effective vcsicular-arbuscular (VA) mycorrhizal fungi could enable the development of sustainable agricultural systems with reduced input of high cost fertilizers. This paper reviews the limited knowledge of the VA mycorrhizal fungal species present in Caribbean agriculture and highlights the need to determine which species/strains are present in Caribbean soils and also their effectiveness. The potential of surrogate plant transformation via genetic engineering of VA mycorrhizal fungi is considered and the possible consequences of releasing genetically modified VA mycorrhizal fungi are discussed.