How do you develop a comprehensive delta-v budget for a multi-year mission?

Delta-v budget accounts for all propulsive maneuvers over mission life. Categories: Orbit insertion - Launch dispersion correction, Orbit acquisition/circularization; Station-keeping - Drag compensation (LEO), N-S and E-W (GEO), Constellation maintenance; Attitude - Momentum dumping (if thrusters used), Reaction control; Contingency - Collision avoidance, Anomaly recovery; and End-of-life - Deorbit (LEO) or graveyard boost (GEO). Development: Calculate deterministic requirements from orbital analysis, Add statistical components (3-sigma dispersions), Include margins (typically 10-20%). Allocation: Propellant mass = wet mass * [1 - exp(-dv/Isp/g0)], Size tanks, structure, thermal control accordingly. Mission extension: Budget for nominal mission with reserves, Extended mission burns into margin. Tracking: Flight operations track usage vs budget, and Reallocation as mission progresses. Documentation: Delta-v budget table with uncertainty, propellant mass, and remaining margin.