People will often believe what they read, even in anonymous notes, and especially if your nuisance shareholder is pushing people's buttons concerning their money. You should definitely go with Steve Rosenstein's very good advice, with a few additions. Part and parcel of coop life is a certain number of oppositional folks who seem to enjoy the power that comes with manipulating opinion. Board members' work will therefore always involve responding to misinformation and continually communicating with shareholders, with clear factual information, so that they know what is going on. My additional advice addresses the dynamic discussed by Frank Lovece in his recent article on the Habitat website. Namely, people with more time on their hands will often win board elections--in spite of a lack of competence--because they use their time for one-on-one interactions with shareholders. Busy professionals - who often have more of the budgetary and managerial skill needed to run a building - are therefore at a disadvantage. You and other board members need to be strategic about including informal discussions with shareholders. People appreciate the give and take of conversations, in which their questions and concerns can be answered, moreso than the one-way communication of written memos. If you split up the work - and track the people you and other Board members interact with - the board can (re)gain shareholder trust and you will have an easier time managing the building.