Too often architects focus on the image and the surface of things in their desire to make a beautiful building. But that’s not how I think. We start with a blank piece of paper, and I never do a sketch first. Instead, we discuss what needs to be done. Architecture is about thinking, researching, being open-minded, and looking at what others did — in different ages, regions, climates, and cultures.

For example, our 1 Bligh tower in Sydney assumed a compact elliptical plan to better integrate with the surrounding buildings, maximize harbour and city views, minimize solar heat gain, and benefit from spatial efficiency. We also lifted the entire structure 20 metres up to give its footprint back to the city; people can enjoy the sun on its stepped plaza. On the other side is an atrium that runs the entire building height. There is a public garden on the roof. It’s all about openness and transparency—the private offices also look onto the atrium. Many clients wouldn’t opt for such an approach on their own. But when you present people with compelling ideas, they often follow. The beauty of the spaces convinced people to rethink their preconceptions. All of those elements together make the building very special. And its elliptical form allows it to curve gently away from the surrounding buildings.

Every decision was based on numerous discussions and experimenting with geometry, space, views, efficiency, functions, etc. We also tested whether a double-skin facade would make sense in Sydney, and it did. The building demands the highest office rents in Australia, but it is also the country’s most sustainable building and very prestigious companies have chosen to call it home, including the Sydney office of the Prime Minister.

First, we do not use more resources than necessary. We aim to be resourceful and disciplined. And we build buildings for people to enjoy. We always think about the experience people would have in our buildings. Nowadays, many people talk about making greener and more sustainable buildings. But can architects honestly say that being sustainable is our primary concern? Are those questions truly at the core of our thinking? I don’t think so. We need to try harder. The problem is bigger than the solutions we can currently offer.

I would add understandability. When we design a building, we hide nothing. I don’t believe in magic. I believe in decisions that are rational, conscious, and reasonable. That’s how solutions can be improved. I don’t get into theoretical or philosophical debates. Architecture should be measurable and tangible. We should think about providing shelter for people and how to solve actual problems. Architecture that doesn’t prioritize those issues is always bad. Architecture is not a caprice but a necessity.

High-tech is a problematic definition for me because it is primarily a style. Many so-called high-tech architects are so enamored of machines that they put them on display. In my view, making a show of them is frivolous: it multiplies surfaces and is a nightmare in terms of maintenance. Machines should be hidden or covered. So, I would hesitate to call my work high-tech.

What I appreciate in the work of some high-tech architects, like Norman Foster, Richard Rogers, and Renzo Piano, is that when Post-Modernism became fashionable, they were not part of the hype. And when Post-Modernism passed, their works looked modern and timeless. They also raised environmental questions. And their buildings are definitely beyond exceptional. All in all, they are experimental architects. But those I admire the most are not only innovative but also combine their work with local traditions and spirit. Particular examples include Arthur Erickson, Harry Seidler, and in more recent years, Glenn Murcutt. Their architecture is honest and site-specific. Every building should respond specifically to its location. But many so-called starchitects essentially do the same building wherever they are invited to build.

That’s not a contradiction — buildings can be both rational and emotional. Our Stuttgart Central Station is rational because of how it occupies its site at the very centre of the city; it is underground and it provides access to a public park. At the same time, it is a stunning building and an emotional, impressive place. Spatial poetics is an extra layer that adds unique qualities. But it is there because there is an absolute need for it in the city.

One of the most beautiful buildings that I admire is Alhambra in Granada. Beauty was, of course, on the minds of this building’s creators, but there were also so many other aspects: to provide shade and calmness, cool air in the garden, to celebrate the sound of water, and so on.

Of course, things like increasing the span and making the lightest construction possible have always been architects’ goals — from the Hagia Sofia to the Gothic cathedrals. Dedication to beauty is an ongoing project. And it is in my genes — I can’t stop thinking about making things beautiful. But I am also driven by my conviction that beauty results from the right decisions. The point is to make buildings seem effortless, meaning no one should see how hard it was to achieve that. It’s like hearing a great pianist’s performance; the beauty goes far beyond technique. Yet the effort is not apparent. For architects, it’s the same. When we see something extraordinary, we tend not to think about the effort put into it or even the price tag, right? [Laughs.] Of course, the outcome should aim at being sustainable.

I would mention places like Switzerland for their very high standards for craftsmanship. They can also afford to build good buildings that are sustainable, safe, and well-composed. But if you are looking for innovation, meaning doing things differently, Germany is still a good place for that. We are not as wealthy, but we are rooted in a tradition of invention. Look at our car industry: There is a drive to do better. Thinking about improving how machines work is very German. Also, we continue to make buildings lighter; an excellent example of that would be Munich Olympic Stadium by Frei Otto. It’s crucial for architects to show a different way of thinking and open up new directions. For that reason, I am also a fan of California — people there are inventive and know how to market their inventions. Not necessarily in terms of architecture and urban planning but how we will live in the future: How to build free-emission buildings and vehicles and produce less CO2. We urgently need to focus on innovation. Of course, we can reduce our demand, but population growth will offset that. We need a new source of energy that is safe and, hopefully, inexhaustible.

Regarding architecture, we should look to Singapore for bringing greenery into buildings, Africa for being resourceful, and major cities such as São Paulo and Mexico City that try to improve conditions in slums and prevent them from spreading. Then there are fashionable centres in California, Copenhagen, UAE, and China, where spectacular architecture is produced often. But I think many of those projects are missing a sense of scale, attention to detail, and, most importantly, focus on people. Architects should think more about repositioning themselves and be more conscious about whom they serve. So often, architects serve dictators, not people. There is a global need for a very different attitude.

Only that it is all a lot of work. I still spend many hours drawing, and with every line I draw, I question if it is the right one. We think about every detail. Mies was right when he said, “God is in the details.” Even the smallest details should be meaningful.