Internal and External Dependencies

Internal and External Dependencies describe the two broad categories a dependency falls into based on where the relied-upon factor originates, distinguishing dependencies on other parts of the same organization from dependencies on parties entirely outside it, a distinction that matters because the team's ability to influence, communicate with, and coordinate around each type differs substantially. This categorization is one of the most fundamental and widely applied dimensions used within dependency classification, since the organizational boundary a dependency crosses tends to shape nearly every aspect of how it must be managed.

Defining Internal Dependencies

Reliance Within the Same Organization

An internal dependency exists when a team's work relies on a deliverable, decision, or resource coming from another team, department, or individual within the same organization, meaning both parties ultimately answer to shared organizational leadership and shared overall objectives.

Shared Organizational Context

Because internal dependencies exist within a common organizational structure, the parties involved typically share access to similar tools, communication channels, and reporting relationships, which can facilitate coordination compared to dependencies crossing an organizational boundary.

Defining External Dependencies

Reliance Outside the Organization

An external dependency exists when a team's work relies on something provided by a vendor, partner, customer, regulator, or any other party operating outside the organization's own direct management structure.

Independent Priorities and Processes

Because an external party operates under its own priorities, processes, and constraints, which are not directly aligned with or governed by the team's own organization, external dependencies typically carry a distinct set of coordination challenges not present with internal reliance.

Why the Distinction Affects Management Approach

Differing Degrees of Influence

Internal dependencies generally allow for more direct influence, since escalation paths exist within the shared organizational hierarchy and organizational priorities can, at least in principle, be aligned to support the dependency being met on time; external dependencies typically offer less direct leverage, often requiring negotiation, contractual terms, or relationship management instead.

Differing Communication Channels

Coordinating around internal dependencies frequently relies on existing internal communication tools and established organizational relationships, whereas external dependencies often require more formal communication channels, such as contracts, service level agreements, or scheduled vendor check-ins.

Differing Visibility Into Progress

Because internal teams typically operate with more shared visibility into each other's plans and progress, internal dependencies can often be tracked with greater transparency than external ones, where the team may have limited insight into the external party's actual status until a formal update is provided.

Risks Associated With Each Type

Risks With Internal Dependencies

Internal dependencies can still be disrupted by competing priorities within the organization, where the other internal team's own commitments and constraints cause delay despite both parties technically belonging to the same organization.

Risks With External Dependencies

External dependencies carry additional risk from factors entirely outside organizational influence, such as the external party's own capacity constraints, differing business priorities, or circumstances unrelated to the relying team's needs altogether.

Practices for Managing Each Type

Managing Internal Dependencies

Internal dependencies benefit from proactive coordination using shared planning processes, direct conversations between teams, and, where necessary, escalation through shared organizational leadership to help align competing internal priorities.

Managing External Dependencies

External dependencies are often managed through more formalized mechanisms, including documented agreements specifying expected timing and quality, regular status check-ins, and, where appropriate, identifying alternative options in case the external party cannot meet the needed timeline.

Applying Extra Buffer to External Dependencies

Given the generally lower degree of direct influence and visibility associated with external dependencies, plans relying on them often incorporate additional schedule buffer compared to plans relying primarily on internal dependencies, reflecting their comparatively higher inherent uncertainty.

Consequences of Not Distinguishing Between the Two

Applying Insufficient Formality to External Coordination

Treating an external dependency with the same informal coordination approach suited to an internal one can leave the team without adequate visibility or influence, increasing the risk of being caught off guard when the external party does not deliver as expected.

Applying Excessive Formality to Internal Coordination

Conversely, applying heavy, formal coordination mechanisms designed for external parties to routine internal dependencies can introduce unnecessary overhead and slow down coordination that could otherwise proceed efficiently through existing internal relationships.

Visual Representation

Dependencies crossing the organizational boundary, shown by the dashed line, carry different characteristics than those remaining within it. This distinction can be expressed as:

Internal and External Dependencies is the classification that determines which side of this function a given dependency falls on, directly shaping the coordination approach best suited to managing it effectively.