How do you manage and control cloud costs on Azure?

This is asked constantly, because uncontrolled cloud spend is a real and common failure.

Visibility first:

• Tag everything by environment, owner, and cost centre, and enforce tagging with Azure Policy. Without tags you cannot attribute a bill, and attribution is what changes behaviour.
• Cost Management budgets and alerts so overspend is caught in week one rather than on the invoice.
• Azure Advisor for concrete rightsizing recommendations.

Then the levers, roughly in order of payoff:

• Turn things off. Non-production environments running overnight and at weekends are the most common waste. Auto-shutdown schedules pay for themselves immediately.
• Rightsize. Instances are usually provisioned for a peak that never arrives.
• Reserved Instances or Savings Plans for predictable baseline workloads — substantial savings for a one or three year commitment.
• Storage lifecycle policies moving cold data to Cool and Archive tiers.
• Watch egress charges, which surprise people because ingress is free.

Note: Framing cost as an engineering responsibility rather than a finance problem is the answer interviewers want.