The Three Horizons model owes its existence to the pioneering work of Bill Sharpe and colleagues in the International Futures Forum, who offered a simple but profound way to understand how systems change. Sharpe didn’t set out to create a management fad; he gave us a language for recognizing when our thinking is trapped in the present, when we’re tinkering at the edges, and when we’re genuinely designing for a different future. His contribution is one of those rare pieces of foresight that becomes more accurate with time, and it continues to guide everyone who works at the intersection of strategy, transformation, and long-term value. If we’re serious about building projects that outlast the turbulence of the moment, we stand on the shoulders of Sharpe’s insight.
Three Horizons, in normal human language

Think of the Three Horizons as three different “worlds” existing at the same time:

• Horizon 1 (H1):
  The world we’re living in right now. Fossil-heavy, wasteful, fragile. Projects are judged mostly on time, cost, scope, and maybe a carbon line at the end.

• Horizon 2 (H2):
  The transition zone. Pilots, prototypes, “green initiatives,” innovation labs. Some of it keeps H1 on life support, some of it points toward something genuinely different.

• Horizon 3 (H3):
  The world we actually need if we want to stay within planetary boundaries and maintain any kind of social stability. Regenerative, fair, low-carbon, risk-aware by design.

If you’re doing sustainability in projects, the question is simple:

Are you polishing Horizon 1, tinkering in Horizon 2, or deliberately building Horizon 3?

Most standards and guides still live firmly in H1. They don’t say that out loud, of course. They use all the right words: climate, equity, resilience, circularity. But look one layer down and you see the same pattern: mitigation, not transformation.

How to spot Horizon 1 thinking dressed up as “sustainable”

You can recognize an H1-era guide in a few seconds. It usually has four giveaways:

1. It treats sustainability as something to “consider,” not something that constrains decisions.
   You’ll see language like “take into account environmental and social issues.” Sounds reasonable. But if there are no defined thresholds, limits, or “this is not acceptable” lines, then nothing really changes. Sustainability becomes a nice-to-have, not a non-negotiable.

2. It piles everything on the project manager’s shoulders.
   The message is: “If you’re a good, ethical PM, you’ll integrate sustainability.” That might sell training courses, but it’s not how systems work. You don’t fix structural problems with individual heroics. If governance, portfolio selection, and incentives don’t change, the PM is being asked to swim against the current with a smile on their face.

3. It loves narratives but avoids mechanisms.
   Older guides are full of thoughtful explanations and good intentions. They talk about responsibility, stakeholders, SDGs, the Triple Bottom Line. But there’s no real operating system underneath: no way to measure whether a project is inside or outside safe limits, no way to compare options beyond “less bad than before.”

4. It stays focused on impact mitigation, not impact generation.
   The best it aims for is fewer emissions, less waste, smaller harm. Horizon 3 asks a different question:
   What positive condition are we building, and how do we know we’re contributing to it?

If you recognize your favorite guide in that list, that’s not an accident. A lot of well-meaning work is still anchored in a worldview where the current system is assumed to be basically fine, and the job of sustainability is not to question it too hard.

That’s Horizon 1.

Horizon 2: The trap that feels like progress

Then there’s Horizon 2, where most organizations like to live.

This is the land of pilots, proofs of concept, and glossy case studies:

• A “net zero by 2050” promise with no binding 2030 plan.

• A slightly greener fuel for the same destructive model.

• Better dashboards for tracking damage we still intend to cause.

Some of these innovations are what I’d call H2-: they make the old system more efficient, less embarrassing, more palatable. You still get the same outcomes; you just feel better about them.

Others are H2+: early signals of Horizon 3. Regenerative agriculture. Community energy. Circular materials. New governance models. They’re fragile, small, and often under-resourced—but they actually point somewhere new.

Most project “sustainability guidance” doesn’t distinguish between the two. If it has a leaf icon and mentions the SDGs, it’s treated as progress. That’s how Horizon 1 keeps winning inside Horizon 2.

Horizon 3: Where P5 actually lives

Now contrast that with the P5 Standard: People, Planet, Prosperity, Processes, Products & Services.

On the surface, P5 looks simple. Underneath, it’s doing something very different from the usual checklists.

P5 doesn’t ask, “Did you think about sustainability?” It asks:

• People: Who is affected, now and later? Workers, communities, suppliers, future generations. What does “do no harm” actually look like in this context? Where can we improve lives, not just avoid complaints?

• Planet: Are we operating within ecological limits, or just slowing down the damage? How does this project interact with energy, materials, water, biodiversity, and land use across the whole life cycle?

• Prosperity: Who benefits, and who carries the risk? Is this project simply extracting value for a few, or strengthening resilience and shared prosperity?

• Processes: Are our ways of working transparent, ethical, and accountable? Or are we relying on hero PMs to patch over structural gaps?

• Products & services: Does what we’re delivering actually move the system toward Horizon 3, or are we just making Horizon 1 a bit cleaner and more digitized?

That’s Horizon 3 territory. It doesn’t assume the current model survives. It assumes the opposite: that the current model is why we’re in crisis, and projects are one of the main levers we have to move beyond it.

Why P5 feels uncomfortable to Horizon 1 authors

If you’ve spent years writing or promoting traditional project guides with a sustainability layer pasted on, P5 is annoying. It doesn’t play along.

• It refuses to keep sustainability vague. It pushes you toward thresholds, not slogans.

• It doesn’t flatter the profession with heroic language. It quietly asks where governance, portfolio selection, and decision rules need to change.

• It exposes the limits of “optimization.” You can’t schedule, risk-log, or offset your way out of a broken system.

And because it’s structured as an operating standard—not a coffee-table essay—it makes a lot of Horizon 1 material look like what it is: beautifully written, structurally harmless.

That’s not an attack on individuals. Many of the people behind those guides care deeply and work hard. The problem is the horizon they’re working in, not their intentions.

So where does that leave project professionals?

If you sponsor, design, or manage projects today, you’re not neutral. You’re shaping the future operating system, one portfolio decision at a time.

You have a choice:

• You can stay in Horizon 1, using frameworks that treat sustainability as a consideration to be weighed against “real” project constraints. You’ll keep delivering projects that look successful on paper and fail in the world.

• You can sit forever in Horizon 2, running pilots that never threaten the core business model. You’ll have great stories, exciting panels, and very little structural change.

• Or you can start operating in Horizon 3, using tools like P5 to treat sustainability not as a bolt-on, but as the design brief.

That doesn’t mean every project becomes a regeneration manifesto. It means:

• You stop calling harmful-but-slightly-less-harmful “sustainable.”

• You align projects with real limits, not marketing language.

• You measure what actually matters, not just what’s easy to report.

• You treat People, Planet, and Prosperity as core performance domains, not as afterthoughts.

The quiet line in the sand

Some guides will keep re-packaging Horizon 1 thinking. They’ll add new buzzwords, refresh the graphics, and talk about megatrends. They will sound current and feel familiar.

But they’ll still be asking the same old question:

“How do we keep doing what we already do, with a bit less damage?”

P5, and Horizon 3 more broadly, ask a different one:

“What kind of projects belong in a world that has to stay within hard limits and still be worth living in—and how do we design, select, and run those projects on purpose?”

That’s the line.

You don’t have to name anyone. You don’t have to attack an association, a credential, or a particular book. You just have to be clear about the horizon you’re choosing to work in.

And if that makes a few authors of old Horizon 1 guides uncomfortable?
Good. Discomfort is what happens when the future walks in and starts asking real questions.