The core metrics for any Indian digital marketing engagement are: website sessions and traffic source split (organic, paid, direct, social), leads or sales generated and cost per acquisition, conversion rate (visitors completing the target action), ROAS for paid campaigns, email open and click rates, and organic keyword ranking changes for SEO. Vanity metrics - follower counts, raw impressions, likes - should be secondary to business outcome metrics. Setting up proper conversion tracking before launching any performance marketing campaign is non-negotiable - without it you cannot optimise toward revenue.