Kai Bunge grew up in Germany fascinated by seeing ideas become built reality – both his father and grandfather were architects, and he helped to construct his family home as a young boy. He chose to study architecture himself and has since remained riveted by the combination of creativity, craftsmanship, design and construction it offers.
Elsewhere in Germany, Siegfried Schindler decided to become an interior architect at the age of 14. He went on to study architecture and graduated with a Master’s degree in 1977.
Both men spent several years separately gaining interior design experience before joining forces to open Partner Ship Design (PSD) in Hamburg, Germany, in early 1991. The firm rapidly developed a reputation for delivering high-quality, innovative design and consultancy services for newbuilds, refurbishments and conversions of cruise ships, yachts and ferries. Spearheaded by Bunge and Schindler, the firm successfully completed 310 diverse projects for major operators including AIDA Carnival Cruise Line, Costa Cruises, P&O Cruises and National Geographic-Lindblad Expeditions.
Now, as Bunge and Schindler pass leadership over to long-term employees Stefan Seidenfaden, Timo Hoogestraat and Silke Förster, they share an insight into their career highlights, the evolution of the industry and more.
Over the past 35 years, Kai Bunge and Siegfried Schindler have successfully completed 310 cruise ship projects together (Photo: Partner Ship Design)
How did you first get into cruise interior design?
Bunge: After my studies, I wanted to gain international experience. First, I worked for an architect in Hamburg, where I participated in a project in Dubai, United Arab Emirates. Next, I freelanced for Meyer Werft’s shipyard in Papenburg, Germany, which was constructing Homeric for Home Lines and needed an interior designer to process information from the plans drawn by shipowner’s architects for the steel construction and fit-out teams. I’d never done these tasks before, but Meyer Werft hired me because I had an architecture degree and spoke English. Everything went well, so I was asked to work on the next cruise ship – Royal Cruise Line’s Crown Odyssey. When I stood under the bow in dry dock in autumn 1987, I knew that my future should be planning and building cruise ships.
Schindler: My passion was furniture design and I worked successfully in that field for two years after graduating university. I then moved to Hamburg, where Howaldtswerke shipyard was constructing the first passenger vessels for the German market. I took my first steps into shipbuilding there in 1979. I was so fascinated by cruise ship construction that I never left the field, and after 47 successful years, I can say it was the best decision I ever made. Shipbuilding has shaped my life for almost half a century.
Which fundamental design principles have underpinned your work?
Bunge: American architect Louis Sullivan said: ‘Form follows function.’ This has always been essential to me and our work at PSD. It’s especially important when designing cruise ships where we need to optimise the limited onboard space. It’s also critical to develop an individual design language for each cruise brand.
Schindler: Nature, everyday life and my surroundings are my greatest sources of inspiration. Observing them closely and reflecting on them fuels my creative work. The variety of light conditions throughout the day, structures from both macro and micro perspectives, colour compositions in spring and autumn, and influences from other cultures – they are all an endless source of inspiration.
Which significant design trends have influenced you?
Bunge: Design trends are a double-edged sword, and they’re not suitable for cruise ship interiors. Five years can pass between the start of a project and the ship’s christening, then it can be another 15 years until the first major renovation, so we must develop long-lasting designs that remain appealing to guests.
However, PSD has helped shape several trends through its work. When sun decks were still large, teak covered spaces filled with loungers, we developed outdoor landscapes. In the early 2000s, we opened up the hull to introduce three deck high glass facades to bring daylight into the heart of the ship. We also incorporated large scale greenery while others used simple planters and flower arrangements.
Schindler: I observe trends with interest, but they have minimal influence on me. Our designs must remain relevant for 15 to 20 years and trends are too short-lived to be a reliable guide. Instead, we produce timeless designs defined by functionality, quality and emotional appeal. We create worlds of vacation experiences, and what better inspiration could there be than nature itself?
PSD helped to create entirely new onboard experiences, such as the club concept, self-service restaurants and the Theatrium, a multifunctional central space spanning three decks with glass walls on both sides. We also developed three-deck-high indoor fun parks with retractable glass roofs and connected them to family buffet restaurants.
PSD has worked on a diverse range of cruise ships, including Costa Cruises’ Costa Smeralda (Photo: Partner Ship Design)
How have cruise ship design briefs changed during your career?
Bunge: The scope and depth of briefings are heavily dependent on the clients. When we first started PSD, briefings were rudimentary, technical and lacking specifications about the design and style. Today, increased competition means cruise lines must clearly define their products to differentiate themselves, but architects can still contribute their creativity and experience.
Schindler: In the 1970s and 1980s, ship design was tailored to an affluent clientele. Ships were smaller, passengers more conservative and the design was functional, classic and maritime-focused. In the 1990s, the middle classes became the target audience and the relaxed ‘club concept’ from land-based resorts was introduced to ships. Buffet landscapes, multifunctional spaces and immersive environments became central design tasks. Today, there’s an enormous range of cruise lines and each one wants to define its own niche. There are fun, family, adults-only, expedition and themed ships, as well as vessels tailored to different cultures. It’s paradise for designers – you can fully unleash your creativity.
Who has been the greatest influence on your work?
Bunge: From an architectural perspective, I’m very impressed by Santiago Calatrava. His constructions and designs, which are based on structures in nature, are ingenious, creative and constructively unique. My greatest interior design influence is Siggi, who has a unique feel for atmospheres, structures and colours. I approach tasks primarily from a structural and constructive perspective, but he taught me how interior design works.
Schindler: First and foremost, it’s the passengers. Their feedback – positive or negative – is passed on by cruise lines and incorporated into our designs. Two individuals also significantly influenced our success: Michael Thamm, a visionary who shaped the cruise market, and Gerry Cahill, who reinvented Carnival Cruise Line during his time as president.
How important are partnerships in the cruise ship interior design sector?
Bunge: My father always said: ‘The architect is someone who has to know little about a lot, and the specialist is the one who knows a lot about little’. This industry is very special and as a designer you need the support of, and cooperation with, suppliers, engineers, shipyards, classification societies and many others who are reliable and willing to innovate.
Suppliers have been particularly important in helping us realise our ideas. It wasn’t easy to find International Maritime Organization-certified materials in the early 1990s, but we worked with suppliers to develop such materials. For example, Hamburg-based greenery firm Dauerflora helped us bring large-scale plants onto the first AIDA Cruises ships. The company’s founder even put some samples into his car, opened the roof and drove along the motorway so he could test the durability of the leaves in strong winds. This led to the first steel pillars decorated with stabilised palm stems and leaves. Today you find trees, hedges and greenery on almost every ship.
Schindler: It’s essential for designers to have a strong relationship with shipyards, outfitters and suppliers to ensure success. Over 47 years, I’ve worked with so many partners that listing them all would be impossible – and it wouldn’t be fair to single out individuals. What I can say is that people in shipbuilding are exceptional because they’re always solution oriented.
PSD has introduced various interior innovations to cruise ships, including the three-deck Theatrium with expansive glass windows (Photo: Partner Ship Design)
Can you share any amusing or memorable stories that illustrate why you are so captivated by this industry?
Bunge: There are many moments I remember fondly – the numerous warm encounters with people, keel layings, christenings, signing contracts and delivering successful presentations after long days of preparation. Another unforgettable moment happened during a design meeting with a shipowner, a shipyard and an outfitting firm, where we were trying to overcome structural challenges to implement a domed ceiling. As people were haggling for space my gaze fell upon the ship’s almost complete, 250-metre steel hull and I couldn’t believe we were arguing over millimetres. It showed me how important small details can be in such a large project, and also that solutions can only be achieved if everyone is involved in the conversation.
Schindler: Many years ago, I supervised the construction of an office building for a shipowner. The construction company brought consultants and lawyers to site meetings – the focus wasn’t to solve problems but assign blame between trades. In 47 years of shipbuilding, I’ve never experienced such a situation in a shipyard. Everyone always shares the same goal – delivering the ship on time – and that can only be achieved through collaboration.
What does the future look like for you and PSD?
Bunge: When Siggi and I established PSD, we deliberately chose not to use our names because we wanted the company to be known for its creativity, expertise, reliability and integrity, rather than who led it. This also made every employee feel at home. We’ve come a long way and the company is even stronger than before the Covid pandemic. It’s time to pass the leadership to a younger generation. However, that doesn’t mean we’ll vanish from the scene; designing cruise ships is in our DNA!
Schindler: Kai and I have worked successfully in the cruise ship market for 35 years. It’s time to embrace the ‘autumn of life’ with all its beautiful nuances.
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