The purpose of this phenomenological study was to explore the musical and inner human processes that emerged in the lived experience of solo and joint free improvisation from the viewpoint of the improviser, also exploring how those processes related to the improviser’s world. The study included eight adult participants, musicians and non-musicians (amateurs), who varied in their improvisational experience as well as in age, personal and professional background. Each participant was engaged in one solo and one joint improvisation (with the researcher) on their chosen musical instruments. Improvisations were followed by an in-depth semi-structured interviews involving immediate impressions of the experience as a whole, followed by listening to the recorded improvisations where participants identified significant musical moments The synthesis of verbal and musical data revealed five interconnected, non-linear phases of the improvisers’ movement toward the attainment of creative freedom. Those were: Acceptance and Trust (letting go of expectations and judgment), Adaptation (moving through uncertainty with self and with another), Emergence (taking individual and social risks toward discovery), Transcendence (experiencing flow and moments of sync) and Expansion (experiencing the joy of individual and mutual creation). These emerged phases portrayed various musical and extra musical dimensions of the improvisers’ way of thinking, searching, acting, being and feeling in and through sound making- from the very beginning to the ending phases of their solo and joint experiences.   Reflecting humanistic-existential thinking and other relevant literature, the findings of the study showed a direct link between individuals’ involvement in improvisation and the development of courage, intentionality, adaptability, vulnerability, and empathy within meaningful musical engagement as essential qualities toward authentic growth. Participants’ musical experiences also showed a link between improvisation and life meaning. They specifically discussed issues of letting go of judgment, developing flexibility, taking personal and interpersonal risks and practicing mindful ways of listening to self and others. Applications of improvisation were discussed in the context of psychotherapy, suggesting a protocol on the conditions, practices and emerging meanings within clinical improvisation work. / Music Therapy / Accompanied by one compressed .rar file.