World Solve — A living repository of problems worth solving.

What World Solve is

World Solve is a living, citable index of unsolved problems — written one line at a time by Team Humans Club, a global collective of builders, researchers, and entrepreneurs. We do not solve the problems here. We Democratize Innovation.

For builders Skip the search for a problem worth your time. Browse a vetted, growing list and start where the gap is real.

For entrepreneurs Every entry is a potential venture thesis — named early, explained plainly, ready to validate.

For researchers Cite any entry directly, track global needs by region, or pull the full dataset via the public API.

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Urban sanitation systems have not kept pace with rapid city growth.

open Africa, Africa

Most African cities lack sewage networks, leaving pit latrines and open defecation common even in dense slums. Decentralized fecal sludge treatment startups are an underexplored business opportunity.

local-regional africa urban sanitation systems have not kept pace rapid city growth cities african global-unspecified informal water climate-environment

WS01533 · Logged by Ian Patel on 2026-07-22T13:46:00Z · Working on: 0

Citation ID: WS01533 Title: Urban sanitation systems have not kept pace with rapid city growth. URL: https://worldsolve.org/index.php?api=problem&id=1533

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1962 public problems
1962 open challenges
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