I have been on retreat with Serenity Retreat twice now and can't recommend it highly enough. Kim has set up something very unique here - it's a mix of the sensible and practical (who likes paying single supplements? who doesn't get hacked off at sharing the bill when you've only had the Greek salad?) and the sublime (it attracts fabulous people - I've never had a boring conversation yet!). I love that, in Nikiana, you get a choice of accommodation depending on your budget - all are great and I totally adored my simple beachfront apartment. You can also do exactly what you want - have a completely reclusive retreat or be super-gregarious. The optional excursions are great value and huge fun. The meditation adds a deeper element and is highly recommended. I was also lucky enough to do a course with Jane Matthews while I was there - also highly recommended. I recently went on one of Serenity's more formal retreats - offering twice-daily yoga and a series of daily meditation slots (plus a period of silence). Absolutely loved that too. I go on a LOT of retreats (it's part of my job) and, hand on heart, Serenity is one of my all-time favourites - right up at the top. It's not super-lush or glam (if you're all about the fluffy bath robes, look elsewhere) but it is jam-packed with integrity and soul.