When a practice becomes widespread enough, then it has ‘gone to scale’. But
increasing the intensity and spread of a particular practice is not a linear or obvious
endeavour.

The paper proposes that going to scale is multi-dimensional and complex. It focuses
on Community-led Total Sanitation (CLTS): an innovation in participatory methodology, as well as a unique approach to sanitation. The paper describes how CLTS offers important lessons to understand spread which is critical for scaling up in an effective way. The main argument is that spread and adaptation are important aspects of scaling up, which is often neglected in the literature.

After a brief overview of CLTS, the paper reviews the literature on scaling-up and
extracts the useful points relevant to CLTS, and highlights the gaps in the literature
around self-spreading movements. A number of case studies of innovative methods
or approaches that have been successfully scaled-up are then considered: PRA,
Reflect, Community Integrated Pest Management and System of Rice Intensification. The author then maps out CLTS experience, outlining the various ways in which CLTS has spread. After considering the various forms of spread, the ‘spatial strategy’ employed by CARE Bangladesh is given specific attention. The paper then discusses how CLTS and other participatory approaches challenge dominant thinking around community developing by critically examining the World Bank’s discourse around Community-based/driven development. The final section offers concluding remarks regarding how to better understand scaling-up and spread.