Endophytes are found within nearly all plants as part of diverse microbial communities. Thriving within their host plants, endophytes benefit from adaptation and protection, surpassing their counterparts in the rhizosphere. Like well-investigated rhizospheric plant growth-promoting bacteria (PGPB), endophytic PGPB employs various mechanisms to enhance productivity and plant growth. The current chapter examines these mechanisms and discusses their potential applications. Endophytes offer environmentally friendly alternatives for agricultural practices, potentially replacing or supplementing chemicals like fertilizers, pesticides, and remediation agents. The interaction between endophytes and plant hormones, garnering attention due to scientific progress and the pursuit of sustainable agriculture, is explored here. Significant insights into the molecular mechanisms driving plant growth enhancement are gained by integrating omics approaches and studying endophyte-related hormones, such as auxins, cytokinins, gibberellins, and abscisic acid. This review aims to consolidate current knowledge and illuminate potential applications for sustainable agriculture. Technological advancements, a shift toward sustainable agriculture, the demand for stress-tolerant crops, and commercial opportunities drive the growing interest in omics approaches and endophyte-related hormones for promoting plant growth.