#  Introduction   Something has shifted at the intersection of AI and data science, and it's changed how practitioners work. The systems deployed today don't just generate a response and stop. They plan. They execute multi-step tasks. They call external tools, evaluate their own outputs, and loop back when results fall short. We're not entering the agentic era anymore. We're living in it. This period is defined by AI systems executing autonomous, goal-directed behavior, and it has rewritten what data scientists actually do day-to-day. The role has always demanded a rare combination of statistical thinking, programming ability, and domain expertise. A fourth dimension is now the baseline: the ability to design, deploy, and evaluate systems that act independently on behalf of users. Ignore this shift, and your productivity will fall behind your peers. Engage with it seriously, and your effectiveness compounds across everything you touch.…