Tomato ranks among the crops of higher economic importance worldwide, with its yield experiencing a reduction of high magnitude due to abiotic stresses such as drought, heat, cold, and salinity. Developing tomato varieties with tolerance to stresses underpins food safety and sustainable agriculture. This chapter examines advanced molecular approaches in breeding to enhance abiotic stress tolerance in tomatoes. It starts with the importance of tomatoes, then the negative impacts of abiotic stresses, followed by an exploration of tomato plant stress-response mechanisms: signalling pathways, and essential regulatory genes. This highlights the role of genetic engineering, transgenic, and CRISPR technologies in enhancing tolerance. The molecular details of each specific strategy for drought, heat, cold, and salinity tolerance are presented. The comprehensive discussion herein outlines the roadmap for researchers and breeders to capitalize on the emerging key points and technologies needed to increase tomato stress tolerance while drawing attention to future research directions.