Read/write social technologies enable rich pedagogies that centre on sharing and constructing content but have two notable weaknesses. Firstly, beyond the safe, nurturing environment of closed groups, students participating in more or less public network- or set-oriented communities may be insecure in their knowledge and skills, leading to resistance to disclosure. Secondly, it is hard to know who and what to trust in an open environment where others may be equally unskilled or, sometimes, malevolent. We present partial solutions to these problems through the use of collective intelligence, discretionary disclosure controls and mindful design.