Understanding and improving informal settlements in African cities

Urbanization stands as a key megatrend that is shaping Africa’s future, while many cities across the continent continue to struggle with the challenges of informal settlements. At a time when COP30, held in Belém, Brazil, is rallying a global ‘mutirão’ — a collective effort — against climate change, this issue’s Focus spotlights the vital importance of elevating local voices and perspectives to drive a parallel mutirão against the unequal conditions of urban informality across African cities.

In many African cities, over half of the population resides in informal settlements marked by insecure tenure, inadequate access to basic services, unsafe housing and socioeconomic marginalization¹. As these settlements continue to expand rapidly and often without regulation, they pose a pressing challenge to achieving sustainable urbanization across the continent. Anchored in the principle of ‘leave no one behind’ (a cornerstone of the 2030 Agenda for Sustainable Development) and recognizing that ‘no one solution fits all’ (particularly in the Global South), Nature Cities has curated this Focus issue to support a global mutirão for improving informal settlements in African cities. Borrowed from the Indigenous Tupi Guarani language, the concept of a mutirão became widespread through collective grassroots efforts to construct informal housing that is needed in Brazil². As mobilized in the second letter from the presidency of the 30th Conference of the Parties of the UN Framework Convention on Climate Change, the 2025 UN Climate Change Conference (COP30), the concept of a mutirão signifies a collective, autonomous and organic effort to tackle urgent challenges. This Focus issue emphasizes that amplifying local voices and perspectives is essential to the success of a global mutirão against the inequality that comes with urban informality in African cities.

The growing availability of geospatial datasets offers a powerful tool for understanding social, economic and spatial inequalities within the informal settlements of African cities. In this Focus issue, an Article by Yu and coauthors leverages such data to examine shifts in wealth inequality and their relationships with the proportion of slum populations. Their analysis reveals that despite a decline in slum populations over the past two decades, wealth inequalities have widened. As highlighted in the accompanying Research Briefing, this work was grounded in fieldwork and collaboration in Kenya and Malawi. Although geospatial data can risk a detached ‘helicopter’³ view, meaningful insights depend on partnerships between international researchers and local experts. Moreover, as Meissner and Pfeffer note in their News & Views, mapping initiatives can help to generate political pressure to improve urban services, but translating data into actionable, location-specific interventions is essential for meaningful change.

Wealth inequality is just one of many challenges that residents of informal settlements face. Limited access to green spaces also affects livelihoods and well-being. In an Article and Research Briefing by Jiao and colleagues, satellite-based mapping of individual trees across 54 African cities reveals a stark shortage of urban trees in the most informal neighborhoods, which highlights the urgent need to integrate green spaces into sustainable urban development. Complementing the pixel-level analysis of satellite imagery, Egyptian journalist Mirna Fahmy’s News Feature offers a compelling narrative from the perspective of local residents, which documents the alarming decline of green spaces in informal settlements in Cairo and throughout Africa. Yet, local communities are responding with resilience, planting and nurturing greenery through grassroots efforts led by social enterprises and local initiatives. As Okyere emphasizes in a Correspondence, these grassroots actions should be further recognized as informal, inventive practices and assemblages that not only shape the African city but also serve as vital processes through which everyday urban life is actively negotiated.

Turning remote monitoring into local action within informal settlements often reveals a deeper challenge: misalignment among urban stakeholders — government planners, researchers and residents. Bridging these gaps requires ground-level engagement, including policy analysis and community interviews. By doing so, an Article by Wesch and coauthors explores how residents in seven South African low-income communities perceive and prioritize quality of life, and uncovers disconnects between state planning and lived realities. Recognizing these conflicting rationalities can foster more-flexible and inclusive spatial decision-making. Zooming in on Makoko, an informal settlement in Lagos, Bakare’s World View highlights tensions between residents and authorities, and underscores the need for bottom-up interventions to safeguard homes, identities and livelihoods. Beyond government–community divides, academic research can also clash with local expectations. In a Q&A, Olumuyiwa Bayode Adegun, who has extensively studied urban heat adaptation in African informal settlements, reflects on community fatigue when research fails to deliver tangible improvements in daily life, and emphasizes the importance of aligning scholarly efforts with real-world improvements to sustain trust and engagement.

By acknowledging these misalignments, contributors to this Focus issue offer local insights and collective views to advance sustainable urban planning. In a Comment, Frimpong and colleagues propose a decolonial urban-planning strategy to tackle climate vulnerabilities in the informal settlements of African cities. Such an approach values Indigenous knowledge and embraces informality as an essential component of African urbanism. Additionally, Sabry’s World View calls for urgent attention to the needs and rights of children in slums, and offers actionable steps and inspiring examples from organizational initiatives across African cities. Furthermore, drawing on the collective views of an interdisciplinary and transdisciplinary group, Borofsky’s Perspective advocates for a data-rich, action-oriented, ethical research agenda to improve infrastructure access in informal settlements, and highlights recent initiatives from African informal settlements that embody these principles.

During COP30’s thematic days on 17–18 November, Indigenous peoples and local communities are taking center stage, with inclusive and grounded solutions prominently showcased. As Myers’s Books & Arts piece highlights, knowing the city in Africa demands a ‘Southern’ approach, in which theorization is relational, personal and rooted in practical engagement, and ranges across formal and informal contexts. Building on this momentum, this Focus issue aims to foster inclusive and grounded approaches that address the unique challenges faced by informal settlements in African cities. We hope the local insights and strategies shared here could inspire researchers, policymakers, practitioners and residents to collaborate in a mutirão effort towards creating urban environments that are equitable, resilient and responsive to the needs of all inhabitants, ensuring no one is left behind.