Mind of My Mind is the second published novel in Octavia Butler's Patternist series, and chronologically it is the second, but the first published is actually fifth in the chronology and the fourth published is first. Confused? Don't be. Stick with publication order and everything will be just fine.
In Patternmaster we are introduced to a future Earth where humanity is divided into Patternists (telepaths), the Mutes (normal humans), and Clayarks (disease altered humans living no better than beasts). The telepaths are linked through something called "The Pattern", hence Patternists.
Mind of My Mind jumps back to a time not far off the present day and none of the future Pattern exists. We are introduced to Doro, a once human who has lived for thousands of years by jumping from one body to the next. He has been selectively breeding families of humans for millenia for telepathic ability and now he has several humans who may have sufficient power and control to take the next step.
Up until Mary, most of Doro's potential telepaths have been failures. Most who have transitioned to be an Active have been unbalanced and a danger. Mary has the potential to be the strongest and the most stable, if she lives through transition from Latent to Active.
What follows is a gathering of telepaths, the rise of Mary, and the origins of the Pattern. While this can be read before Patternmaster or after Wild Seed (which is set even before this book), but publication order is the way to go as Butler reveals this world in a particular way and with each revelation the next becomes more important.
Patternmaster was quite obviously Octavia Butler's first novel. It was decent enough, but not as strong as her later works. With Mind of My Mind Butler has written a much stronger novel which deals more with issues of identity and belonging, but it is also simply a stronger story with greater detail and description and more raw emotion. The first half of the novel is building, building and telling a consistent storyline with shifting viewpoints. Midway through when Mary actually begins building the Pattern Butler's storytelling becomes fragmented in that we are now given scattered episodes about the building of the Pattern. There are greater shifts in time during the second half of the novel, but this too is building to a great conflict and a great confrontation.
Not perfect and not as extraordinary as her later work, Mind of My Mind is a much more accomplished novel than her debut and shows the growth of Butler's soon to be masterful storytelling.