Indiana University-Purdue University Indianapolis (IUPUI) / Emotional communication is fundamental to everyday interaction. How well emotions are communicated is crucial to interpersonal relationships and individual well-being. Emotional communication in instant messaging (IM), however, can be challenging because of the absence of visual and aural nonverbal behaviors. Despite the growing number of technologically-focused solutions for supporting emotional communication in IM, limited design research has been done to study the actual users’ behaviors in communicating their emotion in IM and strategies they use to adapt emotional communication in this medium, with the purpose of establishing design solutions to support users' emotional communication. Connecting several bodies of HCI, design, and communication literature in the context of IM, this dissertation critically examines how users communicate emotion in IM and accordingly establishes user-centered multi-touch gesture based design solutions to support emotional communication in this medium. Understanding how users communicate their emotion in IM, the design issues, and corresponding design solutions help researchers and designers to support the user's emotional needs, resulting in the improvement of emotional communication strategies in IM.