What Is a Vendor Management System and How Can It Improve Your Business?

In more than two decades working with organizations on their external workforce programs, I've watched the same moment play out repeatedly: a senior executive asks a simple question: how many contractors are currently working for us? Nobody can answer it.

It's more common than most organizations want to admit. As companies increasingly rely on external workers, managing that workforce through a patchwork of spreadsheets, emails, and personal relationships isn’t sustainable. In a November 2024 report, the Bureau of Labor Statistics found that 6.9 million U.S. workers held contingent roles as their main job, and that number keeps climbing. U.S. contingent assignments grew 5.6% from 2024 to 2025, outpacing growth in traditional payroll employment. For organizations without a centralized system to manage these workers, the blind spots compound fast.

A vendor management system (VMS) is the infrastructure built to solve that problem. This article covers what a VMS is, what it actually does for your business, and why the technology is only part of the equation.

What is a vendor management system?

A vendor management system (VMS) is a software-as-a-service platform built specifically for managing an organization's external workforce. That includes independent contractors, temporary workers, consultants, and service providers. Essentially, it’s anyone who doesn't receive a W-2 from your organization.

In the staffing context, a VMS manages the full lifecycle of contingent labor: from the moment a hiring manager submits a request for talent all the way through onboarding, time and expense tracking, billing approval, and reporting. Where organizations once relied on instinct, informal channels, and whoever answered the phone first, a VMS brings structure, accountability, and a single source of truth to every transaction.

It's worth noting that "vendor management system" can mean different things depending on the context. In procurement, the term sometimes refers to software for managing supplier relationships, contracts, and purchasing. In the workforce context it refers specifically to the technology that manages external labor programs. That’s what we’ll be referring to throughout this article.

Organizations that manage their external workforce in a decentralized way tend to benefit most from a VMS: large enterprises buying contract labor across multiple departments or geographies, as well as mid-market companies that want to grow their contingent programs without losing control of cost or compliance. The vendor management software market reflects that growing demand: the industry was valued at $10.4 billion in 2025 and is expected to reach $18.76 billion in 2031.

What drives companies to adopt a VMS

Most organizations don't go looking for a vendor management system unprompted. Something breaks first. In my experience, the decision to implement a VMS almost always traces back to one of three problems.

Visibility into the external workforce

The most common trigger is the simplest: leadership doesn't know who's working for them. Contract workers get hired department by department, manager by manager, through whatever agency relationship or personal network happens to be convenient. Nobody has a complete picture. A VMS was built in large part to bring that picture into focus. It pulls every external worker, across every department and location, into a single system of record where they're visible, trackable, and reportable.

Controlling the cost of external labor and services

Once you have visibility, cost surprises tend to follow. Without centralized oversight, organizations can discover they're paying meaningfully different rates for the same talent in different markets without anyone realizing it. At the enterprise level, those gaps aggregate quickly. A VMS captures every transaction, which makes rate variances visible and gives procurement teams the data they need to negotiate from an informed position.

Staying compliant as requirements tighten

Compliance obligations around contingent labor have grown considerably more complex over the past decade. In an unmanaged environment, there's no guarantee that background verifications, non-disclosure agreements, tenure rules, and onboarding requirements are being applied consistently across every hire. Between 10% and 30% of U.S. employers incorrectly classify employees as independent contractors, meaning millions of workers are engaged under terms that may not hold up to regulatory scrutiny. A VMS builds compliance into the process so you aren’t guessing or leaving it to chance.

How a VMS works

Before vendor management systems existed, a hiring manager who needed a contractor did what came naturally: called the agency they'd always used, worked their personal network, or took a meeting with whoever had been in touch recently. The process was informal, inconsistent, and pulled them away from their actual job.

A VMS changes that dynamic. When a hiring manager needs external talent, they submit a requisition through the platform. From there, the requirements get validated, typically with MSP support, to confirm the request is scoped correctly and routed to the right talent channel. The VMS then broadcasts the need to the entire approved supply base simultaneously, giving every qualified supplier an equal opportunity to respond with candidates.

Once a candidate is selected, the VMS manages onboarding, tracks time and expenses, routes invoices for approval, and captures everything in a centralized reporting layer. Hiring managers can stay focused on their work instead of managing vendor relationships, and the organization gains a complete, auditable view of its external workforce in real time.

Benefits of using a vendor management system

Organizations that implement a vendor management system well will see measurable improvements across four areas:

• Complete workforce visibility. Every worker, assignment, and billing code becomes reportable from a single system. For leadership teams that have been operating with blind spots across departments or geographies, that shift supports more reliable workforce planning and budget forecasting.
  
  
• A better contractor experience. In an unmanaged environment, onboarding is often haphazard. Workers show up on day one without system access, a workspace, or clarity on what's expected. A VMS builds consistency into that process, and companies using automation for onboarding reduce time spent on contract generation and compliance verification by 40%.
  
  
• Cost control across markets. With every transaction captured in one place, rate variances that previously went unnoticed become visible and actionable. Organizations that shift from SOW-based arrangements to appropriate contractor roles are capturing labor cost savings of 10% or more. At scale, that spend discipline compounds.
  
  
• Reduced compliance risk. A VMS applies background screenings, non-disclosure agreements, tenure tracking, and onboarding documentation consistently across every engagement, so it’s not left to individual hiring managers. For organizations buying contract labor informally or off-contract, that consistency alone represents meaningful risk reduction.

Why a VMS needs more than technology

A VMS is only as good as the process around it. Put one in place without clear governance and consistent management, and it reverts quickly to what it replaced: people using the tool inconsistently, data entered incompletely, and insights that are too unreliable to act on. In other words, garbage in, garbage out.

The reason is straightforward. A VMS is the system of record; it handles the digital blocking and tackling of daily transactions exceptionally well. What it can't do is learn your organization's culture, anticipate hiring demand before it's been requested, or recognize when a hiring manager is over-scoping a role or buying from the wrong talent channel. Without human intervention, no one is flagging those mismatches before they hit the budget.

Where an MSP fills the gap

What the VMS can't provide, a managed service provider (MSP) can. An MSP provides the governance layer that makes the technology perform: consistent process management, supplier oversight, and the human judgment the platform can't replicate. A good MSP operates as a broker, balancing the interests of the buyer and the supply chain rather than favoring either at the expense of the other.

In my experience, organizations that self-manage these programs can make them work, but they tend to plateau. Without access to cross-client best practices, market intelligence, and a specialist's institutional knowledge, even well-run internal programs eventually run out of lift.

What to consider before adopting a VMS

A VMS implementation is not a small undertaking, and the organizations that struggle with it most are usually the ones that underestimated that going in. Before getting started, there are a few things worth getting right.

First, build your business case fully before going to market. Know what problem you're solving, what success looks like, and how you plan to measure it. Organizations that skip this step often find themselves backtracking to get internal alignment they should have secured before the process started.

Second, plan for resistance. Implementing a VMS means increasing transparency across the organization, and that transparency comes at a cost for some stakeholders. Hiring managers who previously had full control over their vendor relationships and buying decisions will have less. That's not a reason to slow down, but it is a reason to invest in change management and make sure you have the right sponsors in place before rollout.

Third, think carefully about governance from day one. A VMS configured and launched without a clear plan for who owns and manages it is likely to underperform. Ultimately, the technology is the easy part. Execution is what separates a VMS that transforms your program from one that collects dust.

Where the real work begins

A vendor management system gives your organization the infrastructure to manage its external workforce with visibility, consistency, and control. But infrastructure alone doesn't produce results. The organizations that get the most from a VMS are the ones that pair the technology with the right governance, the right process, and the right expertise to run it well.

If you're ready to explore what that looks like in practice, Kelly's MSP team has been building and managing external workforce programs for 30 years. Reach out to get the conversation started.