What Is Best Of Breed Integration? Definition & Examples

Best of breed integration is an M&A approach that preserves the strongest systems from each organisation rather than forcing an immediate wholesale replacement. It can deliver more value and flexibility, but it also increases integration complexity, so identity and access controls must be aligned early to keep the environment manageable.

How Best of Breed Integration Works

Best of breed integration keeps the most capable systems from each organisation and connects them instead of replacing everything at once. That makes sense when the acquired environment has strong point solutions, critical business workflows, or specialised platforms that would be costly or disruptive to rewrite immediately.

The trade-off is that the environment becomes a federation of systems with different data models, trust boundaries, and operating assumptions. The integration effort is therefore less about “moving to one platform” and more about making the surviving systems behave coherently enough for business use, governance, and support.

In practice, the success of this approach depends on whether the retained systems can share authoritative data, enforce consistent access decisions, and expose a manageable operating model. Where they cannot, the result is usually duplicated records, inconsistent workflows, and hidden dependencies that slow the organisation down.

Why Identity and Access Alignment Matters

Identity and access controls are often the first control plane that has to be harmonised because users, admins, integrations, and automation all need predictable access to the retained systems. If authentication, authorization, and role ownership are left inconsistent, the integration may technically work while still being difficult to govern.

This is especially important when inherited systems contain many service accounts, API keys, and third-party connections. NHIMG’s Ultimate Guide to NHIs is useful here because it frames why visibility, rotation, offboarding, and zero-trust thinking become harder as the number of non-human access paths grows.

When integration spans SaaS, cloud, and on-premises environments, access decisions often depend on the weakest trust relationship in the chain. That is why teams should treat early identity alignment as a core integration requirement, not as a post-cutover cleanup task.

Common Failure Modes in M&A Integration

The most common failures are not usually dramatic outages, but cumulative control drift. Different entitlement models, duplicated identities, orphaned integrations, and inconsistent administrative boundaries can leave the combined organisation with more access than intended and less clarity about who owns what.

Integration can also expose latent dependency risk. A system that looked stable inside one organisation may rely on undocumented credentials, fragile API connections, or old SSO assumptions that break once domains, tenants, or directory structures are merged. The more interfaces there are, the easier it is for a hidden trust path to survive the transaction.

That is why inherited integration chains deserve direct scrutiny. Real-world OAuth and token abuse patterns show how third-party access can be turned into broad data exposure, and the same logic applies when M&A preserves multiple platforms with overlapping integrations. See NHIMG’s Klue OAuth Supply Chain Breach, Vercel Context.ai OAuth Supply Chain Breach, and GitHub Repo Breach, Heroku and Travis CI OAuth Tokens for concrete examples of how integration paths become exposure paths.

When Best of Breed Is the Right Integration Choice

Best of breed integration is strongest when the business has a clear reason to preserve specialist systems, and when the organisation can tolerate the governance overhead that comes with that choice. It is often a better fit than immediate consolidation when speed matters, when systems are heavily embedded in operations, or when wholesale replacement would create avoidable business disruption.

The approach is weaker when the combined estate cannot support consistent identity, logging, lifecycle management, or ownership. In that case, the enterprise may gain short-term continuity but inherit a long-term control problem. A selective integration plan works best when it reduces complexity over time instead of simply freezing it in place.

For readers looking for adjacent control guidance, NIST’s Security and Privacy Controls and Cybersecurity Framework 2.0 both map well to the governance, access, and control consistency concerns that emerge during integration.

Risk and Threat Considerations

Best of breed integration can widen the attack surface because it preserves multiple systems, trust relationships, and access paths during a period when governance is already under strain. The main risk is not the architecture itself, but the opportunity it creates for excessive privilege, stale access, and weak oversight across the merged environment.

Failure mechanism: Inherited accounts, tokens, and integrations can remain active after ownership changes, creating a path for unauthorized access, lateral movement, or abuse of third-party connections.

Impact: Data exposure, privilege sprawl, and hard-to-trace access activity can persist well after the transaction closes, especially when offboarding and revocation are incomplete.

Standards & Framework Alignment

This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.

OWASP Non-Human Identity Top 10 address the attack and risk surface, while CIS Controls v8 and NIST CSF 2.0 set the governance and control requirements practitioners need to meet.

Framework	Control / Reference	Relevance
CIS Controls v8	5 — Account Management	Best-of-breed integration must rationalize inherited accounts and access paths.
	6 — Access Control Management	The term centers on aligning permissions across retained systems after M&A.
	15 — Service Provider Management	Integrated estates often preserve third-party connections and delegated access.
Recommendation — Inventory, review, and remove inherited accounts that no longer have a business owner. Standardize access control decisions across merged systems and enforce least privilege. Review third-party integrations and revoke any unnecessary delegated access.
NIST CSF 2.0	PR.AC — Access Control	The concept depends on consistent authorization across multiple retained platforms.
	GV.OV — Governance Oversight	M&A integration requires ownership and accountability for surviving systems and access.
Recommendation — Align access controls across the merged environment before expanding production use. Assign clear ownership for the retained systems, identities, and trust relationships.
OWASP Non-Human Identity Top 10	NHI-01 — Improper Offboarding	Integration often leaves old machine access active after organisational change.
	NHI-02 — Secret Sprawl	Preserved systems often carry API keys and tokens across organisations.
Recommendation — Remove inherited non-human access that is no longer required after the merger. Consolidate and inventory secrets so merged systems do not retain hidden access paths.

Practitioner Guidance

Governance implication: Treat identity ownership, access recertification, and integration inventory as part of the integration workstream from day one. The practical question is not only which systems survive, but which access paths remain trustworthy enough to operate in the combined estate.

Practitioner takeaway: Best of breed can preserve value, but only if the merged organisation can explain and control every retained trust path.

Best Of Breed Integration