A qualitative analysis (The Empirical Phenomenological Psychological method) of interviews involving eight patients (depression, burn-out syndrome, and chronic pain) was carried out in order to obtain knowledge regarding the effects of flotation tank therapy. This knowledge might be helpful for both professionals and potential floaters. The analysis resulted in 21 categories, which were summarized as four themes: (a) experiences during flotation, (b) perceived effects afterwards, (c) technical details, and finally (d) the participants' background, motivation, and expectations. Floating was perceived as pleasant. An altered state of consciousness was induced, varying from a milder state including profound relaxation and altered time perception, to more powerful with perceptual changes and profound sensations such as out-of-body experiences and perinatal experiences. (Contains 1 table.)