As generative AI transitions from experimentation to enterprise deployment, the need for model customization becomes paramount, particularly in complex and regulated industries like healthcare and finance. General-purpose models often fail to meet the specific demands of these sectors, prompting organizations to tailor AI models to their unique languages, workflows, and compliance standards. This customization enables businesses to enhance capabilities, streamline operations, and improve core functions while ensuring safety, alignment, and regulatory compliance. Recent data indicates that 75% of organizations investing in generative AI prioritize model customization, with high-performing companies twice as likely to adapt foundation models to boost efficiency and accuracy. This shift away from larger, more costly models towards smaller, tailored solutions provides substantial long-term cost savings. Customization methods range from simple prompt engineering to complex pre-training, allowing enterprises to unlock agentic AI's potential for autonomous workflow management. Successful AI customization requires strategic planning, careful cost management, and continuous evaluation to maintain alignment with organizational values and regulatory standards.