Hēmi is a board member for Taranaki Mounga Project (a landscape scale conservation project on Taranaki Mounga), Ka Uruora (a social investment initiative that provides housing, savings and financial literacy programmes) and was until recently, a Trustee of Venture Taranaki, Taranaki Arts Festival Trust (TAFT) and WOMAD NZ. He is currently the CEO of Ngāti Tama ki te Waipounamu Iwi Trust, based in Whakatū (Nelson). 

Hēmi has previously held a number of senior executive roles, including CEO of Te Kotahitanga o Te Atiawa Trust, General Manager for Te Rūnanga o Ngāti Mutunga Iwi Trust as well as General Manager at Tourism New Zealand. 

Hēmi has also acted in a senior advisory and negotiation capacity for Te Ātiawa and Taranaki iwi, and most recently with respect to the Mounga Taranaki settlement claim, which was completed in 2024.