Hi-my dictionary sez harm is "injury, damage, hurt, wrong, evil" (to do these is to do harm).  When I did my fourth step, I got a pretty good idea of how I had hurt others, and included acts where I couldn't know the actual effect on others, such as various types of theft, wrong sexual behavior, sins of omission, and so forth.

Harm to me is multi-faceted and may include physical, mental/emotional, social, financial, spiritual aspects. So I looked at the various implications of my interactions, and even my thoughts...what was in my heart.

My fifth step provided me with the majority of my "list" for making amends, and the 8th step only needed to be reviewed and completed, adding one person I had not wanted to deal with one until I knew I had to for my own sobriety. That was a situation where the person had done devestating harm to myself and my child...it was hard to separate that out from anything I did to wrong him, which was miniscule in comparison, and I considered deserved and justified. Had to work that one out in therapy before I could make "spiritual" amends (not safe to make contact).

In some cases, I really wasn't sure if I had harmed someone, so I simply asked them, letting them know why I was asking and that I hoped they could be honest with me. In doing that, there was only one surprise, where I had been clueless. Learning that the person felt wronged by me, and then making the amends, helped our friendship become stronger.