What is Managed Detection and Response (MDR)? (Updated for 2025)

Managed detection and response (MDR) services are threat response services delivered by external (as opposed to in-house) cyber security analysts and experts. It is a multi-layered protection service that can detect and respond automatically to a threat before it becomes a breach.

An MDR team’s primary goal is to prevent security events from becoming breaches, with the service comprising of both technologies and expertise to provide monitoring for, and detection and hunting of, threats to an organisation’s network, computer systems, or physical facilities.

Managed detection and response actions fall within the detect and respond phases of a business’ cyber security posture when they are acting reactively to a discovered threat.

MDR services are increasingly used by businesses due to an increase in cybercrime (with an estimated global cost of over $10.5 trillion in 2025) with their outcome-as-a service cost efficiency enabling organisations to access more sophisticated resources when they are needed — helping keep costs optimised and provide access to resources that might not otherwise be available.

While some organisations might still require a specific level of in-house expertise, the best MDR providers are inherently flexible, making it possible to combine in-house capabilities and external services.

How does MDR Work?

Managed detection and response services relies on a number of simultaneously operated technologies and systems organised by a SIEM (Security Information and Event Management) platform, backed by specialist and experienced experts.

Collectively these systems work to analyse a number of endpoints and attack surfaces for potential threats. If a threat is detected the team then works to contain it before it becomes a security breach before eradicating it entirely. The following securities, techniques and policies are all used within MDR.

Endpoint Security

Endpoint security or endpoint detection is the backbone of any managed detection and response function.

Focusing on monitoring and protecting the devices across an entire network or infrastructure in order to prevent the system as a whole from being exposed by a breach at any specific endpoint, endpoint security systems like Microsoft Defender are designed to detect, locate, analyse, and respond to cyber-attacks quickly. Although it can be deployed in isolation, it is only truly effective with the support of dedicated human management and response resources.

This solution partners incredibly well with MDR due to its focus on isolating and identifying threats before they become a breach. This type of solution delivers the flexible technical foundations that enable a managed service like MDR to be used to best effect.

Threat Hunting and Intelligence

These human-led proactive approaches offer comprehensive coverage of threats that may fall outside the detection net of endpoint security.

Threat intelligence is a forward-thinking function with the aim of providing proactive defence against emerging threats. Using evidence-based knowledge, experts learn about the specific threats and threat landscapes individual businesses are likely to face and then work to minimise the risk and potential impact of these threats before they emerge. At Six Degrees, we issue regular updates to ensure that you’re kept informed on the latest risks and are best placed to make any in-house changes needed to maximise the capabilities of our MDR services.

Conversely, threat hunting seeks to find potential threats that could have already slipped past existing detection and security nets. By assuming compromise has already occurred, experts work backwards to discover signals, anomalies, and behaviours to discover threats and threat actors before containing them and building systems to prevent repeat incursions.

Incident Response

The response segment of MDR, incident response is a structured process executed by a specialist team that contains and eradicates an active threat once it has been detected or a breach that has already occurred. A dedicated team follows a set process to detect and analyse the issue, deploy a tailored solution to contain the problem, and then oversee eradication, recovery, and post-incident analysis to develop learnings for future cyber security conduct.

What are the Benefits of Managed Detection and Response Services?

There are a number of benefits to engaging with a trusted third-party partner such as Six Degrees for MDR services, especially over employing an in-house team to handle the same responsibility. These benefits include:

• Proactive Monitoring and Detection: Managed Detection and Response services provide around-the-clock, 24×7 real-time, proactive alert management, detection and response for comprehensive protection of your system infrastructure.
• Dedicated Cyber Security Expertise: MDR teams are comprised of dedicated experts who are proficient and highly experienced in dealing with a range of incident and threat situations. An MDR partner guarantees access to expertise without having to invest in full-time staff (including specialists) who aren’t always needed.
• Rapid Response: Outsourced teams provide incredibly fast response times when incidents or breaches occur, ensuring threats and breaches are handled as soon as possible and preventing any additional impact from a delayed response.
• Access to Economies of Scale: Monitoring a system for threats requires relatively minimal resources, whereas responding to an active incident is often an all-hands-on-deck situation – situations which have a large resource disparity which presents a challenge to in-house teams. Outsourced MDR services alleviate this challenge with the ability to scale up or down depending on the organisation’s needs, improving cost-efficiency.
• Post-incident Management: Once the incident has been resolved the MDR partner remains on-hand and active, helping organise recovery efforts including logging and aftermath management, ensuring the partner organisation can recover completely.

What Types of Tools and Functions are Used in MDR?

The following tools and technologies are used regularly by Managed Detection and Response teams within their service offering.

• SIEM: A SIEM or Security Information and Event Management is a centralised log, alert and investigation system that offers information sharing and management for threats and detections that span across multiple sources or surfaces. Six Degrees manage and review automated incident response using the advanced and cloud-native Azure Sentinel security information and event manager.
• Endpoint Defender: Endpoint defenders are sensor-based systems that provide detection coverage across an entire network or infrastructure with the capability to deliver response actions.
• SOC/CSOC: A SOC (security operations centre) provides 24×7 situation monitoring and investigation as well as communication across teams and organisations for response alignment and coordination.
• NGAV: Next-Gen Antivirus is an additional detection tool for endpoints which enables more comprehensive threat alerts for malware and ransomware.

How Does MDR Differ from Other Managed Cyber Security Services?

Managed detection and response is one of a number of managed cyber security services offered by third-party partners. While many of these services can sound similar to each other, and have similar acronyms, each have unique service offerings, limitations and purposes.

MDR vs. MDA

Managed Detection and Alert can be treated as a “light” version of MDR, providing detection and monitoring services across a number of security endpoints. However, the managed service does not include any incident response capabilities – either containing or responding – once a threat is detected.

MDR vs. Threat Intelligence

Threat intelligence is an independent service that provides solely expert-conducted research and investigation into the threats a business could face, with follow-up actions that help prevent and minimise risk from these threats. However, it does not include endpoint detection, threat hunting or any incident response.

Additionally, some capabilities from MDR could be delivered within an in-house monitoring and response team known as a Cyber Security Operations Centre (CSOC). However, an-house CSOC operation is likely to be cost and resource intensive and, similarly to the response elements of MDR, only see part-time utilisation. Utilising a managed service like MDR, therefore, is a far more efficient option.

MDR vs. MXDR

MDXR stands for Managed Extended Detection and Response, which is a multi-layered comprehensive service that offers unparalleled vigilance and protection. The key difference between MDR and MXDR is the latter’s coverage of both endpoint and cloud surfaces, offering complete threat detection coverage.

When Should Organisations Use MDR Services?

There are several specific scenarios in which businesses should engage with a partner for MDR services.

If an organisation doesn’t have in-house detection and response capabilities, using an MDR service partner is an ideal solution. The managed service partner can provide ready-made, tailorable solutions that deliver specific expertise and experienced capability for the business in a resource-efficient, high-ROI format.

Similarly, if the business is one of almost 44% of all UK organisations currently facing a cyber security skills shortage and needs access to expertise on-demand, an MDR partner can provide this through their managed service team.

In some cases, the threat landscape a business is facing is extremely complex or requires a more proactive approach to threat defence. In these instances, MDR services can provide the additional skills, resource, and management capabilities to minimise risk and the impact of potential threats.

How Does MDR Help Establish a Strong Cyber Security Posture?

Engaging with an MDR partner is crucial for building strong detect and respond capabilities for a complete and well-rounded cyber security posture.

Having full-coverage detection facilities is key to identifying threats before they become breaches. MDR provides this through both robust endpoint security in endpoint defender and NGAV, and through expert-led threat intelligence and threat hunting.

Being able to respond to emerged threats is essential for minimising risk and impact of attacks, and MDR services provide rapid response functions to ensure businesses can contain breaches and eradicate threats.

How Can Managed Detection and Response Services from Six Degrees Help Improve Your Cyber Security?

MDR involves relying on a strategic partner to keep your organisation safe. You need to take that choice seriously. At Six Degrees, our MDR services combine best-in-class technology with industry-leading expertise and a cyber security philosophy that stresses automation, flexibility, and defence-in-depth within the context of an ROI-centred focus on outcomes. Here are three components you need to consider:

Your cyber security journey

The threat landscape never stands still — neither can your response. Our cyber security strategy seeks to align your risk exposure with your risk appetite and constantly updates best practices to minimise internal and external threats to deliver an efficient and effective outcome that matches your security posture.

The importance of Microsoft Defender for Endpoint

Our MDR solution is powered by Microsoft’s leading-edge endpoint security technology, and combines Microsoft Security Centre with Azure Sentinel and our Six Degrees CSOC for a multi-layered approach to cover endpoints, networks, and cloud services. For businesses embedded within the Microsoft ecosystem, this delivers unbeatable comprehensive support within a holistic and effective solution. It also delivers the automation needed to respond in real-time and prevent threats from becoming a breach. Discover more about our technology and security partnerships.

Doing more with less

We believe that cyber security should drive opportunities, rather than hold you back. By selecting flexible, cost-efficient and modern solutions, better outcomes can be achieved at a lower cost — enabling your organisation to demonstrate the true ROI of security and stay ahead of risks.

Tailored to your business

Any incident response team requires the ability to monitor a system, deploy automated responses in real-time to manage and delay a breach, and then deploy human expertise to remediate the threat. At Six Degrees, we deliver this outcome using a combination of people, processes and technology — and you can access that expertise within a cost-efficient and sophisticated framework. Every organisation and industry is unique. Our bespoke deployment, configuration and management ensure that our solution is tailored to you.

A future-focused, fully-accredited cyber security solution

Flexible and responsive cyber security capabilities are needed now more than ever, particularly in the context of today’s complex operating landscape. We provide access to a best-in-class solution, delivering economies of scale while allowing you to sidestep the cyber security skills shortage.

Our cyber security teams supply the professional capabilities and cyber threat intelligence you need to focus on your core business, safe in the knowledge that your systems are secure and ahead of cybercrime trends. Our accreditations and cyber security certifications, including GIAC, CHECK, Crest and CISSP, enable us to connect that with your entire technology base.

At Six Degrees, we will:

• Review your existing infrastructure and provide an expert solution configuration.
• Strengthen your cyber security defences and respond automatically to threats.
• Use technology to automate the blocking and containment of threats.
• Deploy human expertise to manual triage incident prioritisation and alert analysis from a UK-based CSOC.
• Deliver threat analytics and investigation enabled by on-demand access to expertise.
• Guarantee security monitoring in real-time 24×7.

The reputation and business cost of security breaches is so much higher than their prevention. MDR is the best way to address cyber security now and in the future. MDR from Six Degrees will deliver defence in depth, enabling you to do more with less and guiding you safely on your cyber journey.

Cyber Security Services

Strategy and Advisory 

• Information Security Manager
• Cyber Security Incident Response
• vCISO

Consultancy

• Cyber Security Assessments
• Penetration Testing
• Red Teaming
• Frameworks and Certifications
• Penetration Testing as a Service
• Phishing and Scenario Testing

Managed Security Services

• Managed Detection and Alert
• Managed Detection and Response
• Threat Intelligence 

Further Reading and Resources 

• MDR Webinar: Aftermath of SolarWinds
• What is Cyber Security?
• The Crucial Role of a Managed Service for Business Mobiles
• How to Choose the Right Managed Service Provider

Additional reading: Four Ways Strategic Partnerships Improve Cyber Security