Ethical investing in commercial activities is a topic which has received considerable attention of late. This has occurred in the areas of company law at all levels, with the concerns of consumers in relation to the production of products, and also in trust law, in particular superannuation trusts. Superannuation Trusts are of particular significance as they have become significant institutional investors in a number of substantial commercial activities. Ethical investment which requires the trustees to take account of issues other than financial when investing is seen to run counter to traditional trust law principles. Relevant issues relating to ethical investing include: human rights and labour concerns, environmental and moral issues such as investing in the alcohol and tobacco industries. This paper focusing upon superannuation law in the Australian and New Zealand jurisdictions considers the investment obligations of trustees in superannuation trusts. Such obligations closely resemble what may be referred to as traditional or core obligations of trustees. It acknowledges that difficulties arise when attempting to include ethical considerations in investment decisions with trust property. Having acknowledged this, the paper in upholding the place of ethical investing in the current environment proceeds to outline a means by which ethical investing can be adopted without compromising the position of trustees in any manner and which still focuses upon the best financial interests of the beneficiaries.