Authority is only one source of movement
Cross-functional work depends on people whose priorities, measures and constraints may differ from yours. A title cannot resolve all of those differences.
Understand what the other person protects
Stakeholders may be protecting quality, speed, compliance, customer trust, resources or reputation. Influence improves when your proposal acknowledges those realities.
Reduce the cost of agreement
Clear requests, realistic next steps and visible trade-offs make it easier for others to engage without feeling that they are accepting hidden obligations.
Treat resistance as information
Resistance often reveals an unmet concern, competing commitment or lack of confidence. Explore it before repeating the same argument more forcefully.
Communication creates impact when it helps people see clearly, decide confidently and move together.