This master thesis analyses notational and textual methods of composing for improvisation. Ways of integrating space for improvisation, guided at different levels depending on the amount of information given, into a composition. The least guided being a one- or two-words exhortation (e.g., “play free!”) up to a clearly defined progression, with a specific number of bars, chords and rhythm. How the players involved in each compositional project reacted − intuitively, intellectually and with their instruments − to the given information has also been analysed. I have integrated information and space for improvisation in four of the five projects I wrote during my studies. Two original arrangements for big band, one composition for small chamber group, and eleven shorter pieces for sextet performed in my final exam concert. I also mention some compositional aspects and challenges I experienced in writing for wind ensemble, where I decided to not include any space for improvisation. Throughout the thesis I also describe situations, experiences, and anecdotes from my own background as instrumentalist and improviser, and how much they sometimes influenced the next step taken. This serves the purpose of putting the creative process of composing and improvising, the choices made while working, in a broader contest of life experienced.