The Beclin 1 network regulates autophagy and apoptosis. Beclin 1, a mammalian homologue of yeast Atg6, plays a central role in autophagy, a process of programmed cell survival. It interacts with several cofactors to regulate the lipid kinase Vps-34 protein and promote the formation of Beclin 1-Vps34-Vps15 core complexes, inducing autophagy. The BH3 domain of Beclin 1 is inhibited by Bcl-2 or Bcl-XL, and this interaction can be disrupted by phosphorylation or ubiquitination. Caspase-mediated cleavage of Beclin 1 promotes cross-talk between apoptosis and autophagy. Beclin 1 dysfunction is implicated in disorders such as cancer and neurodegeneration. This review summarizes new findings on the Beclin 1 network in cellular homeostasis, focusing on the cross-regulation between apoptosis and autophagy. Autophagy is an essential process that involves the selective degradation of cellular components. It has three main types: macroautophagy, microautophagy, and chaperone-mediated autophagy. The process of mammalian autophagy involves several steps, including initiation, nucleation, elongation, closure, maturation, and degradation or extrusion. Autophagy depends on Atg5/Atg7, is associated with LC3 truncation and lipidation, and may originate from the ER membrane and other membrane organelles. Recent studies have identified an Atg5/Atg7-independent pathway of autophagy. Beclin 1 is required for both Atg5/Atg7-dependent and -independent autophagy. However, Beclin 1-independent autophagy is evaluated in various experimental settings, complicating the discernment of the role of these individual pathways. The mammalian target of rapamycin (mTOR) is a central element in signaling cell growth and enhancing protein translation. When inhibited, mTOR induces autophagy, and its reactivation terminates autophagy and initiates lysosome reformation. Autophagy serves an adaptive role in protecting organisms during periods of cellular distress. In rare settings, the self-cannibalistic functions of autophagy may be deleterious and lead to cell death. Beclin 1 is a BH3-only domain autophagy protein. It is important for the localization of autophagic proteins to a pre-autophagosomal structure. Beclin 1 contains three structural domains: a BH3 domain, a central coiled-coil domain, and an evolutionarily conserved domain. The ECD is essential for Beclin 1's ability to mediate autophagy and inhibit tumorigenesis. Beclin 1 also contains a short leucine-rich amino acid sequence responsible for its nuclear export signal. Anti-apoptotic Bcl-2 family members interact with the BH3The Beclin 1 network regulates autophagy and apoptosis. Beclin 1, a mammalian homologue of yeast Atg6, plays a central role in autophagy, a process of programmed cell survival. It interacts with several cofactors to regulate the lipid kinase Vps-34 protein and promote the formation of Beclin 1-Vps34-Vps15 core complexes, inducing autophagy. The BH3 domain of Beclin 1 is inhibited by Bcl-2 or Bcl-XL, and this interaction can be disrupted by phosphorylation or ubiquitination. Caspase-mediated cleavage of Beclin 1 promotes cross-talk between apoptosis and autophagy. Beclin 1 dysfunction is implicated in disorders such as cancer and neurodegeneration. This review summarizes new findings on the Beclin 1 network in cellular homeostasis, focusing on the cross-regulation between apoptosis and autophagy. Autophagy is an essential process that involves the selective degradation of cellular components. It has three main types: macroautophagy, microautophagy, and chaperone-mediated autophagy. The process of mammalian autophagy involves several steps, including initiation, nucleation, elongation, closure, maturation, and degradation or extrusion. Autophagy depends on Atg5/Atg7, is associated with LC3 truncation and lipidation, and may originate from the ER membrane and other membrane organelles. Recent studies have identified an Atg5/Atg7-independent pathway of autophagy. Beclin 1 is required for both Atg5/Atg7-dependent and -independent autophagy. However, Beclin 1-independent autophagy is evaluated in various experimental settings, complicating the discernment of the role of these individual pathways. The mammalian target of rapamycin (mTOR) is a central element in signaling cell growth and enhancing protein translation. When inhibited, mTOR induces autophagy, and its reactivation terminates autophagy and initiates lysosome reformation. Autophagy serves an adaptive role in protecting organisms during periods of cellular distress. In rare settings, the self-cannibalistic functions of autophagy may be deleterious and lead to cell death. Beclin 1 is a BH3-only domain autophagy protein. It is important for the localization of autophagic proteins to a pre-autophagosomal structure. Beclin 1 contains three structural domains: a BH3 domain, a central coiled-coil domain, and an evolutionarily conserved domain. The ECD is essential for Beclin 1's ability to mediate autophagy and inhibit tumorigenesis. Beclin 1 also contains a short leucine-rich amino acid sequence responsible for its nuclear export signal. Anti-apoptotic Bcl-2 family members interact with the BH3