<p>Tillering is a complex developmental process in cereal crops, regulated by an intricate network of genetic, hormonal, and environmental signals. Key regulators, including <i>TB1/FC1</i>, <i>IPA1/SPL14</i>, and strigolactone-associated genes, integrate cues from plant hormones, light, sugar, and nitrogen to control tiller initiation, bud outgrowth, and overall plant architecture. Although substantial progress has been made in identifying these genes and regulatory modules, gaps remain in understanding their dynamic interactions across developmental stages and under varying environmental conditions. This review highlights advances in functional characterization of tillering genes, QTLs, and regulatory networks in wheat, rice, and barley. It emphasizes the integration of environmental interactions, such as genotype-by-environment effects, with molecular and metabolic signals, as well as the potential of GWAS, multi-omics approaches, and CRISPR-based functional validation for uncovering causal regulators. Translational applications for breeding cereal ideotypes with optimized tiller number, nitrogen use efficiency, and grain yield are also discussed. This synthesis provides a framework for researchers and breeders to exploit the integrative regulation of tillering in cereal improvement programs.</p> Graphical Abstract <p></p>