Paul Boissevain was born on 19 December 1922 at Hilversum, Netherlands. He retained Dutch nationality all his life and did not join the RIBA. He married fellow archiect Barbara Joan Osmond n Eton, Buckinghamshire in early 1947. The practice actually began in 1947 in Dublin as there was no work in the UK after the Second World War. Boissevain returned to the UK to teach at the AA in the session 1950-51 but it is not yet clear how long he continued teaching there. His first client was Shell for whom he designed refineries.

Paul Boissevain had two older brothers who ran the Merchant Adventurers Company (it is not yet clear what range of appliances this company manufactured in the mid-1960s). It was very much a family business: Walter Boissevain, its managing director, was also in charge of design and development; his brother Roland Boissevain was director in charge of marketing; Paul Boissevain acts as a consultant designer to the company. He designed the Trimline light fitting which became an international success. The Design Journal of 1968 published the following regading the Trimline light fitting:

Made by Merchant Adventurers Limited, Feltham,Middlesex. Designed by Paul Boissevain, DipArch, MSIA.

The Trimline light fitting shows every sign of becoming a substantial international success. It can be used as a wall or ceiling fitting, indoors or out, and is ideal for kitchens, bathrooms, halls, passages, porches, garages. It is convenient to mount dust-tight, washable, and made of unbreakable polypropylene. Bulb-changing is simple, the snap-on diffuser being removable with a coin. The fitting looks neat and unobtrusive and provides well diffused lighting. Its design takes full advantage of mass-production methods to achieve a competitive price.

Merchant Adventurers decided to design the Trimline because it was felt that a lowcost, mass-produced fitting was needed both at home and overseas. The relative advantages of plastics, glass, and metal were considered, a plastics being chosen because it was easy to mould accurately, could therefore give neat junctions, and allowed a simple snap-on method of attaching the diffuser.. A separate colour-finishing operation for the gallery was also avoided. Being unbreakable, polypropylene had additional advantages in needing only simple packaging for distribution and export; it also made the fitting ideal for exterior, as well as interior use.

The various adaptations required to suit different electrical standards abroad were carefully considered. For instance the gallery incorporates holes to meet all international fixing standards and, where a terminal block is needed, this is simply pushed into a keyway moulded into the gallery. Costs were kept low by minimising the number of parts and designing for simple assembly.

Merchant Adventurers is very much a family business: Walter Boissevain, its managing director, is also in charge of design and development; his brother Roland Boissevain is director in charge of marketing; and a third brother, Paul Boissevain - who is in private practice as an architect - acts as a consultant designer to the company and is in fact responsible for Trimline.

The Trimline represents an important step in Merchant Adventurers' expansion programme. Since the war the company has grown continuously and in 1965 the size of the Feltham factory was doubled. This gave the necessary production capacity both to start exporting seriously, to tackle retail markets for the first time, and to continue expansion for the company's main architectural market. The Trimline is being used as a spearhead in a rapidly expanding export drive and overseas shipments are already exceeding home deliveries.

Mr Walter Boissevain is convinced that a consistent design policy - reaching from the first conception of the product, through development, to its packaging - is essential to commercial success. "Design means change, and a company can only progress through change. A design policy which is backed and understood at the top means that change will be welcomed as progressive, logical and desirable."

Approximate prices: 1021H (60w, pearl grey) or 1022H (60w, slate black) £1 11 s 3d; 1024H (100w, pearl grey) or 1025H (100w, slate black) £2 9s 2d.

The Trimline's polypropylene base is either pearl grey or slate black; for bulb-changing its snap-on diffuser is easily removed with the help of a coin. The fitting is waterproof, dust-tight, and unbreakable; it can be used indoors or out, mounted on the ceiling or a wall.

The Trimline light fitting became an international success and the No.1 best seller selling over 1,000,000 pieces. There is also the ‘Elipse’ lamp in the V&A - this won a Design Award and the 'Decolurme' table lamp in the Geffrye Museum, its shade made of anodised aluminium. It featured in the 1951 Festival of Britain on South Bank - as an example of high quality industrial design.