Identifiers are an essential component of online communication. My research focuses on the ways that social, technical and policy factors affect people's behavior with online identifiers. For example, my research demonstrates that people separate both business and professional roles by communicating with separate identifiers. People may have different identifiers for technical reasons, such as difficulties in configuring settings. In addition, corporate security policies place restrictions on people's communications which influences the way people manage identifiers. I conducted a series of in-depth interviews with two groups sampled from different populations.