In this paper, we reflect on our experiences teaching and working with mathematics teachers in Canada, Ghana, India and Swaziland to explore challenges and opportunities for creating mathematics tasks for peace and sustainability. Our exploration of these experiences is oriented around our interest in embedding peace and sustainability into mathematics education following the Sustainable Development Goals identified by the United Nations. We claim that attention to local contexts affords mathematics educators a medium for engaging in authentic, meaningful and context-driven mathematics tasks that address issues of local environmental, cultural and societal concerns. However, we argue that globalisation has already colonised local communities. The associated "technoscientificity", along with the conservative nature of textbooks, time constraints and the dominant force of poverty remain hindrances in creating mathematics tasks that are issue centric and socially relevant to address concerns of the local community. We end this paper by suggesting a development of a mathematics task to illustrate the possibility of creating what we call a "situated mathematics task" for students that respond to issues of local community using rural Ghana as a context.