The Handbook of Online Counseling is a foundational work for psychosocial counseling on the internet. In addition to well-founded contributions to the theory of online counseling, the book provides comprehensive information on the possibilities and application areas of this form of counseling. Renowned experts from Germany, Austria, and Switzerland set a standard for the field of professional online counseling for the first time. Areas of email counseling are represented alongside forum and chat counseling, as well as insights into the field of mobile media. Important methodological concepts are presented and conveyed in a practical manner. The spectrum ranges from the four-slide concept to narrative and systemic approaches, as well as the potential use of online supervision. In the area of target group-specific online counseling, the handbook offers insights into couple counseling and women-specific counseling.