M365 Messaging & Collaboration Architect – 11929HSARCHITECT

Contract London, UK Posted 14 hours ago 620 – 725 per day Inside IR35 – 4 days onsite We are working with a leading organisation to recruit an experienced Microsoft 365 Messaging & Collaboration Architect to provide architectural leadership across its enterprise Microsoft 365 environment.

This is an excellent opportunity for an experienced Solution or Enterprise Architect with a strong technical background in Microsoft 365, particularly Exchange Online, Microsoft Teams, Microsoft Purview and enterprise messaging security.

You will be responsible for defining the architectural strategy, technical roadmap and design standards for messaging and collaboration services, ensuring solutions are secure, scalable, resilient and aligned with wider business objectives.

Although architecture-led, this role requires someone who remains technically credible and hands-on, with the ability to challenge designs, make complex technical decisions and provide practical engineering guidance.

Key Responsibilities

• Enterprise Architecture & Strategy
  • Define the strategic roadmap for Microsoft 365 messaging and collaboration services.
  • Develop enterprise reference architectures, technical standards and design patterns.
  • Own the architectural direction for Exchange Online, Microsoft Teams, Microsoft Purview and related Microsoft 365 services.
  • Evaluate emerging Microsoft technologies and define adoption strategies.
  • Align technology roadmaps with business objectives and enterprise architecture principles.
• Solution Architecture & Technical Leadership
  • Produce high-level and low-level solution designs for complex Microsoft 365 programmes.
  • Act as Design Authority for messaging and collaboration solutions.
  • Provide architectural leadership across enterprise transformation and migration initiatives.
  • Review and validate technical designs, ensuring alignment with security and architectural standards.
  • Guide engineering teams through complex implementations and technical challenges.
• Security, Governance & Compliance
  • Define secure-by-design architecture across Microsoft 365 services.
  • Lead architectural design for Microsoft Purview, Defender for Office 365 and enterprise email security solutions.
  • Define governance frameworks covering information protection, DLP, retention and compliance.
  • Own messaging security architecture, including Proofpoint integration, mail flow, SPF, DKIM and DMARC.
  • Work closely with Cyber Security teams to embed Zero Trust principles and strengthen the security of collaboration platforms.
• Transformation & Innovation
  • Lead Microsoft 365 transformation and modernisation initiatives.
  • Define the architecture and adoption strategy for Microsoft 365 Copilot and emerging AI capabilities.
  • Support secure enterprise AI integration and governance.
  • Identify opportunities to improve collaboration services and the modern workplace experience.
  • Influence technology investment decisions and long-term platform roadmaps.
• Stakeholder Engagement & Governance
  • Build strong relationships with senior technology leaders and business stakeholders.
  • Work across Enterprise Architecture, Cyber Security, Identity, Infrastructure and Engineering teams.
  • Lead design reviews and provide architectural assurance.
  • Mentor engineers and technical SMEs, promoting architectural best practice.
  • Represent Messaging & Collaboration within enterprise architecture forums.

Essential Skills & Experience

• 8+ years’ experience designing and delivering Microsoft enterprise collaboration platforms.
• Extensive architectural experience across Microsoft Exchange Online and Microsoft Teams.
• Proven experience developing enterprise architecture strategies, technical roadmaps and design standards.
• Experience leading Microsoft 365 transformation programmes.
• Strong knowledge of Microsoft Purview, Microsoft Defender for Office 365 and Microsoft 365 governance.
• Experience architecting enterprise email security solutions, ideally Proofpoint.
• Strong understanding of Microsoft Entra ID, Conditional Access and Zero Trust principles.
• Experience with Exchange Hybrid environments and complex migrations.
• Knowledge of PowerShell, Microsoft Graph and Microsoft 365 administration.
• Strong understanding of mail flow architecture, DNS, SPF, DKIM and DMARC.
• Experience producing HLDs, LLDs, reference architectures and technical design documentation.
• Proven experience working within Enterprise or Solution Architecture functions.
• Excellent stakeholder management skills, with the ability to influence senior technology and business leaders.

Desirable Experience

• Microsoft 365 Copilot architecture, readiness and transformation.
• Global or multi-region Microsoft 365 environments.
• Mergers, acquisitions and tenant consolidation programmes.
• Regulated financial services or highly governed enterprise environments.
• Teams Phone, SharePoint Online and OneDrive architecture.
• Azure Automation and Microsoft Power Platform.
• AI governance and Microsoft Fabric integration.
• TOGAF or equivalent architecture framework.
• ITIL and Agile delivery methodologies.

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