MDR: What Managed Detection and Response Does for Business

Managed Detection and Response (MDR) is the service category that delivers SOC-quality threat detection and incident response capabilities to businesses that can't justify building those capabilities internally. MDR providers operate the EDR or XDR platform, monitor alerts 24/7 with analyst review, investigate suspicious activity, and respond to confirmed incidents on the customer's behalf. For most SMB and mid-market businesses, MDR is the right way to consume threat detection. Here's what it includes and how to evaluate providers.

What MDR Actually Includes

A real MDR service covers:

• Platform operation — the underlying EDR/XDR platform deployed, tuned, and maintained by the provider
• 24/7 monitoring — security analysts watching alerts continuously, not "after business hours we'll get to it"
• Threat hunting — proactive search for indicators that automated detection might miss
• Investigation — when alerts fire, analysts investigate to determine if they represent real incidents
• Containment actions — for confirmed incidents, immediate containment (isolating endpoints, killing processes, blocking accounts) on the customer's behalf
• Incident response support — beyond initial containment, support through the full incident response cycle
• Reporting — regular reports on detected threats, blocked activity, and recommendations
• Continuous improvement — detection rules and policies updated based on emerging threats and customer-specific learnings

What MDR Is Not

To distinguish MDR from related categories:

• Not EDR alone — EDR is the tool; MDR is the tool plus 24/7 analyst capability
• Not antivirus — different category entirely; MDR is detection and response, not just prevention
• Not managed firewall — overlapping but distinct; MDR is endpoint-focused with network correlation
• Not SIEM-only — SIEM provides correlation and visibility; MDR provides operational response on top
• Not vCISO — strategic security advisory is a different service; MDR is operational

The MDR Vendor Landscape

Major MDR providers in SMB and mid-market deployment:

• CrowdStrike Falcon Complete — Falcon EDR plus 24/7 SOC coverage from CrowdStrike
• SentinelOne Vigilance — SentinelOne EDR with managed analyst layer
• Sophos Managed Threat Response — Intercept X EDR plus managed SOC
• Arctic Wolf — independent MDR with strong SMB focus
• Huntress — SMB-focused MDR with strong MSP channel
• Red Canary — detection-focused MDR with quality reputation
• Microsoft Defender Experts — Microsoft's managed offering on top of Defender for Endpoint
• MSP-delivered MDR — many MSPs deliver MDR as a service layer on top of their EDR platform of choice

For SMBs, the choice often comes down to existing platform investments (Microsoft Defender Experts if heavily Microsoft-centric, MSP-delivered if you have a strong MSP relationship), budget tier, and the specific feature set needed.

How to Evaluate Providers

Key dimensions for MDR provider evaluation:

• Underlying technology — which EDR/XDR platform; how its capabilities map to your environment
• Analyst depth — how many analysts, what tenure, what certifications
• Coverage hours — true 24/7 or business hours plus on-call
• Response authority — what actions analysts can take without customer approval; what requires approval
• Time-to-respond SLAs — measured response time on confirmed incidents
• Customer visibility — what the customer sees about the provider's work; what reporting is available
• Threat intelligence — what feeds the platform; how detection content updates
• Customer references — talking to current customers of similar size and industry
• Pricing model — per-endpoint, per-user, or tiered
• Exit terms — what happens to data and configuration if the relationship ends

The Practical Recommendation

For SMB and mid-market businesses without dedicated internal SOC capability, MDR is the right model for threat detection. The alternative — buying EDR and hoping someone reviews the alerts — typically results in alerts going unaddressed and the security investment failing to deliver value. The math works because the MDR provider amortizes analyst expertise across customers, making 24/7 SOC coverage affordable at SMB scale.

At Leonidas, MDR is delivered through our managed security partner — we help you scope, select, and oversee MDR engagements as part of our cybersecurity consulting practice. If you're scoping MDR for your environment, a conversation with our team can map what fits your situation.