Lake Como
Every participant fishes a shared Italian lake and decides each month how many days to go out. Individually rational choices quietly drain a common resource. Self-interest meets collective survival.
When rational choices ruin everyone
Lake Como is a sustainability simulation built on a real situation among the fishermen of the famous Italian lake. It turns an abstract idea — the tragedy of the commons — into a tense, personal experience: keep your own livelihood without exhausting the resource everyone shares.
Tragedy of the commons
A realistic setting to feel how individually rational decisions can add up to a collectively irrational outcome.
A shared resource
Everyone draws from the same lake. Over-fishing by one shrinks the catch — and the future income — of all.
Competitive decision
Players directly experience the tension between short-term profit and the long-term sustainability of the resource.
Highly configurable
Instructors tune costs, prices and parameters to fit their teaching goals — no technical skills required.
You fish on Lake Como
A simple, vivid premise drawn from a real situation at the Italian lake — and the basis of a genuinely hard collective-action problem.
The setup
You earn your living fishing the lake, alongside others competing with you. Each month you decide how many days — up to 28 — you will go out. You carry €3,000 of fixed costs (boat rental, gear and your living allowance), pay €50 a day in petrol whenever you fish, and earn €1 for every kg you land.
But you are not the only one on the water. The lake holds a finite stock, and the more everyone fishes, the fewer fish each day yields next month. Will you survive the coming months?
Starting parameters
| Fixed cost | €3,000 / month |
| Variable cost | €50 / day |
| Revenue | €1 / kg |
| Catch (healthy lake) | ~200 kg / day |
| Fishing days | 0–28 / month |
| Lake stock | 20,000 kg |
The question the whole simulation turns on: how many days will you fish before the lake runs dry?
The trap, made tangible
Three forces pull at every decision. What is best for you, right now, is exactly what — multiplied by five — destroys the lake for all. Drag the slider and watch it happen.
Your self-interest
To cover €3,000 of fixed costs you need to fish about 20 days a month. The rational move is to fish hard.
Fish moreThe shared lake
The stock is finite — 20,000 kg. Every day fished by anyone removes fish that will not be there next month.
Finite resourceThe collective outcome
If all five fish 20 days, 20,000 kg are taken — the entire lake. What is rational for each ruins them all.
CollapseLake resource simulator
Assume all five fishermen fish the same number of days, on a full lake (month 1).
Illustrative model grounded in the engine constants (catch ≈ stock ⁄ 100 per day; €50 petrol; €3,000 fixed; €1 ⁄ kg). The bind: the ~20 fishing days you need to break even, repeated by five, are exactly what empties a 20,000 kg lake.
The rhythm of every month
A short cycle repeats over the configured months. Each round, every participant commits at once — then the shared lake reacts to what they all did together.
Decide your days
Choose how many days — 0 to 28 — to fish this month.
Everyone fishes
All participants draw from the same lake at once.
Income statement
Catch, costs and net income are tallied for each participant.
The lake updates
The stock falls with total fishing — or recovers if spared.
Next month
Repeat, now with a richer or a poorer lake.
Monthly fishing decision
Each month, participants decide how many days — 28 at most — to fish, balancing revenue against fixed and variable costs.
Shared-resource competition
Everyone draws from the same lake. Over-fishing by one player depletes the shared resource and cuts everyone's future income.
Profit maximization
Players seek to maximize cumulative net profit, navigating the tension between self-interest and collective sustainability.
Instructor debrief
After the run, instructors access comparable results for all participants, enabling efficient debriefing sessions.
What participants take away
An experiential route into sustainability, game theory and collective action — anchored in Hardin's tragedy of the commons and consolidated in the debrief.
Sustainability in business
Deepen understanding of sustainability and its implications for modern business operations.
Decision-making under complexity
Cultivate decision-making skills to address complex scenarios and devise sustainable business solutions.
Collaborative problem-solving
Engage in collaborative problem-solving, especially in situations mirroring the tragedy of the commons.
Insight through debriefing
Harness insights from comprehensive debriefing sessions to foster ongoing learning and sustainable strategies.
Game theory in practice
Feel the gap between the Nash equilibrium and the social optimum — and why communication changes the game.
Negotiation and collective action
Practice building agreements — quotas, rotation, side-payments — that let a group escape the trap together.
Pedagogical anchor: Hardin's tragedy of the commons, experienced first-hand and formalized, with optional ties to Ostrom's work on governing shared resources.
The lake keeps the score
Each participant gets a full income statement every month — and the shared stock tells the deeper story: as the lake thins, every fishing day yields less and earns less.
Income statement
Revenue, variable cost, fixed cost and net income — itemized each month.
Cumulative profit
The survival score: who is still in business as the months pass.
Trends and the lake
Track catch and stock over time — the shared resource that connects every player.
Comparable across cohorts
A unified results view lets instructors compare participants across sessions — for example, groups that were allowed to communicate versus those that were not. The contrast is the lesson.
Built to be configured
Lake Como's signature is its flexibility: a real-time panel to run the room and tune every lever, so the same engine fits a 30-minute energizer or a deep ESG session.
Live monitoring
See who is connected, who has played and the state of the lake, round by round.
Tune every parameter
Set fixed and variable costs, price per kg, number of months and days — no technical skills needed.
Pause and resume
Freeze the room for a negotiation, then resume automatically on the next round.
Compare groups
Run parallel lakes — with and without communication — and contrast the outcomes at debrief.
AI assistant
Optionally give participants an in-game AI chat assistant for guidance.
OptionalRound timer
Show a countdown each round to add time pressure and keep the whole group in sync.
OptionalTips and news
Surface start-of-round tips and an optional, AI-driven news feed for context.
OptionalRooms and alerts
Assign physical or virtual rooms and push real-time alerts to participants.
OptionalWhere the lesson is landed
The fishing stops and the reckoning begins. Whether the lake survived or collapsed, the debrief turns the experience into a transferable model of collective action.
Introduction
Frame the lake, the rules and the survival goal. Participants are fishing within minutes.
Set the rules of engagement
Decide whether the group may talk. The same engine, with and without communication, tells two very different stories.
Play the months
Run the rounds. Pause to let agreements form — or watch them break under temptation.
Debrief and generalize
Compare the lakes, name the mechanism, and connect it to climate, water, fisheries and shared budgets.
Discussion questions that drive it home
Did your lake survive the full run, or did it collapse? At which month did the trouble become visible?
Was the rational individual choice — fish enough to cover your costs — also the choice that doomed the group?
Did any agreement emerge? Who defected first, and what happened to trust afterwards?
What separates the Nash equilibrium from the social optimum here, and what would close the gap?
Which real-world commons does this mirror: fisheries, water, emissions, a shared team budget?
Which solution would you trust most: regulation, quotas, communication, or privatizing the resource?
The insight to land
No one set out to destroy the lake — yet rational, self-interested choices did exactly that. Naming the mechanism and exploring the exits — communication, binding agreements, regulation, ownership — is the moment sustainability stops being a slogan and becomes a design problem.
Lake Como at a glance
Everything you need to position, schedule and run the simulation.
Pairs naturally with Hardin's The Tragedy of the Commons and Ostrom's work on governing common-pool resources, and with negotiation and collective-action courses.
Common questions answered
It describes a situation where the users of a shared resource, acting independently and rationally, deplete it through their collective action, even when that serves nobody's long-term interest. Lake Como turns it into an experience you live rather than a concept you are told about.
Between 30 and 90 minutes, depending on how many months you schedule. A common shape is ~10 min of set-up, ~25 min of rounds and ~20 min of debrief.
There is no limit. Each lake holds around 5 participants competing for the same stock, and several lakes can run in parallel; the instructor panel follows them all in real time.
Fixed and variable costs, price per kg, number of months and maximum days per month are all set from the game management dashboard, with no technical knowledge required.
Yes, and it is the main pedagogical lever: the same engine produces two very different stories. The unified results view lets you contrast the groups that could talk with those that could not, right in the debrief.
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General inquiries
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(+34) 877 245 676Technical support
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