Burkhard Varnholt is chief investment officer of Bank Sarasin. The Basel-based bank manages more than 50 billion euros (about $74 billion) of assets, mostly from the wealthy. He tells The Wall Street Journal Europe about his preference for sustainable funds, the technology sector and emerging-market investments.

We see a broadly increasing interest for sustainable or socially responsible asset management processes. This, in our view, is a sea-change in investor attitudes.