Self Disclosure and Assertive Behavior Characteristics Among Counseling Students at Satya Wacana University Sumardjono Padmomartono Adhi Krisna Maria Agustin Guidance and Counseling Study Program, Satya Wacana Christian University sumardionopm(5)staff. uksw.edu ABSTRACT This article describes self-disclosure characteristics among 83 guidance and counseling students in the areas of their living concerns, namely: 1) 69, 9% students have opened about their beliefs, thoughts and emotions on religion/ spirituality. 2) 68, 7% students are self- disclosing about their interests, their likes, including views, feelings, and appreciation of a person, place or thing. 3) 63, 9% students are frequently eager to reveal private truth about themselves, are honest and seeking others to know them better. 4) 54,2% students are frequently reveal their intimate matters such as sex and willingly discuss their sexual needs and views as well as 22,9% high self-disclosing students who have shared themselves fully and in details of their intimate matters. 5) 53,0% students have opened their thought and feelings about their relationships with their friends as well as 30,1% high self-disclosing students who have opened themselves in details and have the tendency to let themselves to be known in their relationships. Within students assertive behavior: 1) 54,2% students is categorized as high aggressive behavior, only the behavior of 26,5% students, is categorized as very low as well as low aggressive behavior. 2) 51, 8% students are categorized having low non-assertive behavior, whereas only 8, 4% students are categorized having very low non-assertive behavior. Keywords; self-disclosure, assertive behavior, psychological well-being Introduction Jourard integrated self-disclosure with the concepts of self, mental health and communication, defining the "self" as the person's subjective side, his thoughts, feelings, beliefs and wants, emphasizing the importance of self-disclosure, or letting another person knows what one thinks, feels and wants as the most direct means of realistically knowing one's self and thereby achieving a healthy personality integration. Jourard's thesis suggests the degree of self-disclosure to significant others as important for psychological well-being (Jourard, 1959) A Ifdil (2013) wrote that communication will be more effective whenever individuals are capable and eager to express their ideas and feelings openly and smoothly. This personal capabilities and eagerness were defined as self- disclosure. Furthermore, Ifdil 201