Mary was working from written music on a stand. I happened to see one of the pages and what she was doing was way more abstract and varied than what could have possibly been written on the page, and yet she seemed to maintain her concentration on the notation even during long periods of free improvisation. I asked Mary about this process and this was her response.
“With Tomeka's music, there is quite a variety in how the compositions are structured. Some of the tunes are way more open, in which case I am reading less and interpreting more, and others are more highly structured. If you see me staring at the page, I might be reading or following a solo form to improvise over. However, it's just as likely that I might not be reading at all and my eyes just happen to stay focused on the page after I've finished the notated portion. This happens sometimes too.
But regardless of what I'm reading, I do try to let the composition guide the direction of the improvisation. Even if I'm not playing over a form, the written material that comes before and/or after is still integrated into improvisational sections. For me, this is what ties it together into a coherent piece of music and gives each piece its own identity.” (Mary Halvorson)