Salesforce's Technology, People, Innovation, and Learning (TPIL) team shares how they scaled agentic AI adoption across thousands of engineers. Rather than treating it as a technology rollout, they framed it as an organizational learning challenge. They developed a four-level Proficiency Level (PL) Framework — AI-Assisted, AI-Validating, AI-Orchestrating, and AI-Native — grounded in mindset and behavior change rather than tool-specific metrics. Supporting programs included AI camps, weekly coaching sessions, and manager guides. Success was measured not by course completion but by observable shifts in how engineers thought and asked questions about their work. Four key principles emerged: scale shared expectations before scaling practices, treat proficiency as a journey not a certification, measure behavior change over attendance, and prioritize learning culture over any single framework.