Parts work in this context refers to  a way of working proposed by Janina Fisher within a framework of structural dissociation. The idea is that we all have different parts, eg, attach, cry for help, going on with normal life, which play out in our lives in different ways. Generally, our relationship to our parts is on a spectrum from fully integrated to autonomous dissociated parts depending on the complexity of the trauma we have experienced. The theory is that if we understand our current distress, anger, self protection, etc, as communication from parts and learn to develop our curiosity, we can find our way to more integration. My image of it is that when we experience things that assault our system in some way, we package it up and leave it in the past and it stays frozen in time so that we can carry on with normal life as best as we can. The emotions, the meaning making from those experiences leak through into the present as intrusions with no timestamp or context, and our job is to go through something like the wardrobe in Narnia and collect those parts, update them and bring them back out with us where we can integrate their gifts instead of banishing them to a different world. It's like internal family therapy where everyone is welcomed, heard and respected and communication between parts is developed and more teamwork established where different parts needs are known and met. It's a long term process, which needs commitment and persistence, especially if there is not much safety in the system. The idea is that with practise you become better at identifying parts and differentiating them from a strengthening going on with normal life/ wise part as internal safety builds and hence so does emotional regulation. It's an embodied practise and can really calm outdated coping strategies which undermine daily functioning.