This guide examines five leading Kubernetes monitoring platforms — New Relic, Datadog, Prometheus + Grafana, Dynatrace, and Elastic Stack — highlighting that effective cluster observability requires unified visibility across metrics, logs, and traces. The right tool depends on team size, cluster complexity, budget, and existing stack integrations. The article recommends prioritizing automatic resource discovery, real-time alerting, and AI-assisted correlation to reduce mean time to resolution during production incidents.