Beyond the Hype: Core Principles for Building Credible Outcomes Marketplaces

Social outcomes marketplaces (platforms for transacting measured, valued, and unitised impact) have graduated from theory to operational reality, exemplified by live platforms like the Common Good Marketplace (CGM) and the World Economic Forum’s accelerating work on Tradeable Impact. The opportunity now is one of scale: unlocking the full potential for social impact and driving efficiency at a global level. However, as a recent Social Outcomes Conference (SOC25) roundtable confirmed, scaling these systems is not straightforward, and their continued success is far from automatic.

The discussion was based on a set of "wicked questions" – paradoxical challenges that force participants to confront the necessary trade-offs between opposing goals. Rather than arriving at a polished consensus, the group identified that the credibility of these markets relies on managing inherent conflicts: between efficiency and relationship, standardisation and context, price and value. The following four themes represent not solved problems, but the core design tensions that practitioners must actively balance to define the future of tradeable impact.

A central paradox lies in balancing market efficiency with the relational dynamics essential for social change. While marketplaces aim to create liquidity and reduce friction, evidence from outcomes-based contracts shows that embedded relational practices create resilience.

Lessons from voluntary carbon markets offer a cautionary tale: when impact is "unitised," crucial nuances are lost. A marketplace that prioritises transactional speed risks devaluing the very context that makes an outcome meaningful. This is especially true in a new market. Before liquidity exists, suppliers and buyers aren't just transacting; they are co-creating the very concept of value. This requires deep trust.

Therefore, relational practices are not a legacy feature to be "engineered out." They are a form of essential market infrastructure. The most successful platforms will be those that make relationship-building systematic, using tools like transparent governance, structured pre-transaction dialogues, and dynamic performance reviews to build lasting confidence.

Valuing impact is complex and all valuation models have strengths and weaknesses. Cost-based valuation can stifle innovation, while cost-savings logic often undervalues outcomes that are harder to quantify. But beyond the technical models, there’s a relational dimension that’s just as critical: the language of value must resonate with both buyers and suppliers.

Currently, this dialogue is hindered by information asymmetry: suppliers know the true cost of delivering quality, while buyers often rely on generic benchmarks or assumptions. This asymmetry exacerbates the tension between parties already motivated by (sometimes) opposing incentives (buyers seeking efficiency, suppliers needing sustainability) creating a recipe for price pressure. We’ve seen this dynamic play out across carbon markets, where market prices can fail to cover the true costs of delivery.

This dynamic is particularly damaging because social impact does not scale like traditional goods. While infrastructure projects benefit from declining marginal costs, people-intensive interventions often face flat or rising costs as they reach harder-to-serve populations. In a forward purchase context, this raises a critical question: should prices fall over time as efficiencies emerge, or increase to reflect the higher costs of reaching the most vulnerable?

Marketplaces can help narrow the asymmetry gap by making reference values visible, displaying both "cost anchors" (delivery reality) and "value anchors" (benefit to society), and accumulating transaction histories that reveal "shadow prices" over time. Linking valuation not just to delivery costs but to the depth, durability, and relevance of the outcomes — their true social value — is essential.

Standardisation is a fundamental need in outcomes marketplaces. It provides a common denominator that underpins risk and performance management, allows for clearer reporting, and gives buyers and suppliers better information for decision-making. With consistent categories and metrics, outcomes can be assessed side by side, and projects can contribute to broader portfolio goals.

But this comparability comes at a cost. If rigid standardisation "flattens" local realities, it risks alienating suppliers, disempowering beneficiaries, and misrepresenting the work. A project serving a high-cost, hard-to-reach population cannot be "flattened" into an average metric without distorting its true value. Furthermore, a fragmented landscape of competing standards creates its own risk, where the market may default to the best-marketed claim rather than the most rigorous one, for example.

The design challenge is to make room for both, defining high-level outcome categories that support comparability, while allowing structured space for local value expression in pricing and monitoring. At CGM, for example, this means applying a standardised process and impact model that ensures consistency across valuations and issuances, while allowing parameters, requirements and assumptions to vary according to context.

The concept of "additionality" is often a source of confusion because definitions from carbon markets don't map neatly onto social outcomes. In carbon offsetting, financial additionality (asking "would this have happened without my funding?") is paramount to justify the offset. But outcomes-based finance often works differently.

Payments are typically made for results, usually retrospectively. This structure removes delivery risk from the buyer and creates space for suppliers to innovate and compete on quality, while opening the door for diverse actors (concessional funders, commercial investors, and outcome payers) to participate in the financing scheme. In this context, financial additionality is far from irrelevant, but it plays a different role than in offsetting markets.

Instead, impact additionality becomes the non-negotiable anchor. This is the proof, through rigorous baselines and counterfactuals, that the claimed outcomes would not have happened otherwise. This is the bedrock of the market's credibility.

The discussion around additionality, therefore, is reframed. Buyers are not underwriting a fixed plan; they are becoming catalytic funders, enabling future, adaptive impact. This also clarifies the debate around timing. Retrospective issuances are not "old" impact; they are the proof of concept and the trust-building mechanism required to unlock the forward purchase agreements that projects and a maturing market ultimately need.

These four principles — integrating relationships, anchoring in value, balancing standards, and clarifying additionality — are not just technical tweaks. They are the core design philosophy. The tensions they represent are not bugs to be fixed, but the central, dynamic challenges that must be continuously managed. How we choose to build these "soft" elements into the hard architecture of our marketplaces will determine whether they truly fulfill their promise.

This post reflects just one part of a much broader conversation. If you're working on outcomes marketplaces or navigating similar tensions, we’d love to hear from you. What angles have we missed? What challenges or innovations are you seeing in your own work? Reach out to us, we’re keen to learn, collaborate, and continue building this field together.