I struggled with the exact same question the last few days. Semantically both have the same features. You can find an informed comparison here: http://devtionar

I struggled with the exact same question the last few days. Semantically both have the same features. You can find an informed comparison here: http://devtionary.com/?p=89 http://devtionary.com/?p=89 My initial preference was Less, because sass seemed framgmented with 2 syntaxes, and also less seemed more aesthetic, but I ended choosing Sass for the following reasons: * Sass has Compass built over it http://compass-style.org/docs/ http://compass-style.org/docs/ and this alone is the biggeast win over Less Compass is a framework that comes with a foundation of components : - compass core http://compass-style.org/docs/reference/compass/ http://compass-style.org/docs/reference/compass/ - many plugins for different needs (search github for compass), special mentioning Susy liquid grid framework https://github.com/ericam/compass-susy-plugin https://github.com/ericam/compass-susy-plugin - with Compass I can monitor a whole directory of templates at once, and have them instantly compiled when I save from the editor, not sure if Less can do this * Aptanta Studio 3 and few other IDE's know to syntax highlight sass and scss, not sure about less * If you don't like the indentation syntax you can use the curly Scss, Scss and Sass are interoperable, you can call one from the other and vice versa * The ruby version of Less is deprecated and I write a ruby based project (indeed, not all HN users are pythonists) Moreover, I don't like the idea on compiling the templates client side (as in less.js) and waste precios miliseconds, nor use an external interpreter (node.js)