THIRTY may not seem like a great age, but in the world of contemporary business, reaching that maturity is certainly a cause for some celebration. When it has been attained by an independent design consultancy that has stayed rooted in the quarter of Glasgow where it began, and which is unarguably emblematic of the change in the city over those three decades, it seems like the ideal excuse to put out the bunting and have a street party. You feel sure Ross Hunter and Janice Kirkpatrick would stylishly reinvent the occasion with just the right mix of respect for tradition and contemporary pizzazz.

Hunter and Kirkpatrick’s company is called Graven Images, although these days that is more snappily shortened to “Graven”. “People tended to call us that, so it became our trading name,” says Hunter. “We do more than just images,” adds Kirkpatrick, a tad more spikily.

That is the way a conversation with them goes. There is much finishing of one another’s sentences, as you might expect of a couple who have shared a personal as well as a professional life for more than three decades. It is usually Hunter who appears the more practical and, perhaps, pragmatic. Kirkpatrick adds the abstract notions and confrontational assertions. It is not difficult to see why, and how, the team works.

The couple met in the mid-1980s at Glasgow School of Art: he studied architecture, she graphic design. On graduation they dispensed with the tedious business of job-hunting and immediately established their own practice. They might have taken their inspiration from the architect of the original building at their alma mater. Like Charles Rennie Mackintosh, whose input ran from bold building shapes to details of soft furnishings, the concept of Graven Images was of a complete design service, rather than specialising in one particular area of work. Perhaps that was originally the necessity of accepting any jobs they could get, but it now embraces the realm of ideas and concepts as well as physical objects and as easily as the public realm of the city’s streetscape.

Just as crucially, however, the couple started their company at a time when Glasgow was waking up to its own creativity and the possibility of using that to reinvent itself.

“We started the company in January, but we were still signing on. We were on the Enterprise Allowance Scheme, which gave you £38.60 a week, but you got to keep what you earned over and above that. You had to have had 16 weeks of unemployment to qualify,” says Hunter.

Countless new young business were established that way at the time, the pair remember, and they were all supportive of each other.

“Then it was about partnerships and making things better,” says Kirkpatrick. “I hate that adversarial Dragon’s Den thing ¬– all about how to get huge very fast.”

Graven has grown over the past three decades, but at its own pace, and has reached a size where the couple employ a team that enables them to do everything they want to, but which Hunter can’t see becoming any larger than it is now.

“We can now take on a number of bigger projects at the same time – but sometimes it is the wee projects that are much more interesting.”

“Big organisations are often extremely dysfunctional,” adds Kirkpatrick, “and we’ve learned how different businesses work and about their common problems.”

It is an area that she moved into, with the benefit of her design training, and it is part of the Graven philosophy that all businesses could do with a little more creative input into their thinking, and rather less reliance on staff with qualifications in business administration.

“Trained creative people can help with creative problems: there is a chauvinism from people who have come through business schools towards folk with an arts background. They want to develop an idea using numbers, rather than writing it, or making a drawing or a model. The best solutions are all these things in combination, but the spreadsheet rules . . .”

In the early days of Graven Images, Hunter and Kirkpatrick had a mission to persuade people that investing in design was worthwhile. Now they often talk about how establishing a “brand” can be a strategic organising tool for a company.

“In 1986 ‘brand’ was a new word, and so was the idea of corporate identity. No-one was taught how to pick apart the idea of a ‘brand’”

By the time of the construction of the Scottish Parliament building at Holyrood, however, it was in the head of every child. When primary pupils were asked to put paintings of themselves on the hoardings around the site, many of these “selfies” featured prominent sportswear labels.

“It is still a mystery how design works. It is a mixture of intuition and process – and the better the latter is, the better the former becomes. And education is still not alert to that.”

The work of the Graven consultancy is now all around the world, in hotels and British Airways departure lounges, and you don’t have to look far for it Glasgow. The new Riverside Campus of Glasgow College (previously Glasgow Nautical College on the south bank of the Clyde) has interiors by Graven. So will the new home for the Hunterian at Kelvin Hall in the joint development by the University of Glasgow and Glasgow Life. So does BBC Scotland’s new home at Pacific Quay, and the offices of Stefan King’s GI group at its old place at Queen Margaret Drive. Graven designed the logo for the Tunnel nightclub, the Drygate micro-brewery’s bar and restaurant in the East End, the Tinderbox coffee houses in Byres Road and Ingram Street round the corner from their studio, and the signage that designates the entrance-ways to Glasgow’s Merchant City where the firm is still based.

In 2008 the company moved from its first home in Candleriggs to what had previously been the Dispatch Bay of The Herald’s offices in Albion Street, where the trucks delivered rolls of newsprint and vans set off daily with copies of The Herald and Evening Times. Which is fitting, as the consultancy was involved in a redesign of The Herald in the 1990s. Although they no longer live there, having their business in that part of the city is still important to Hunter and Kirkpatrick.

“The Merchant City is still not quite finished, it has a very slow gestation but it is getting there. Everything is a bit well-behaved now, though, it is all a little too clean and tidy.”

But in the 1980s it was a statement to set up shop in the area at all, when architecture and design offices tended to be centred on Park Circus, beyond Charing Cross towards the West End. But, as the couple point out, there are hardly any kindred spirits there now. Back then, the fact they were near the temporary offices for the City of Culture was more of an asset.

“We did the poster design for shows by Peter Brook and The Wooster Group and those were important seed projects for us. In the years 1988 to 1990 Neil Wallace and Bob Palmer at the 1990 office were important clients.”

The staging posts over that decade were 1990, 1996 – when Glasgow put on a huge visual arts programme, despite having lost a civic “year of” title to the North East of England – and 1999, when the city was the UK’s capital of Architecture and Design. Those were the days when the local authority showed a level of strategy and ambition which went beyond a spreadsheet and the total number of bed-nights sold in city hotels, and the atmosphere fostered was crucial to the success of the fledgling design company.

However, at a time when the architectural bravery of St Peter’s Seminary at Cardross has been brought to public attention with NVA’s Hinterland, credit should go to the Archdiocese of Glasgow for writing the first cheque to Graven Images. The mosaic that the young design company produced for a chapel in Yoker was consecrated with a vigil mass by a priest and congregation apparently entirely unconcerned by the potentially blasphemous name of the new design house. It had not been the only option on the table, although Kirkpatrick instantly denies Hunter’s suggestion that Cowboy Outfit was ever a serious contender.

In the 1990s bars and restaurants gave Graven Images much of their business, and the partners say that many of the innovations they introduced then are now finding their way into the work they do for workplaces, with the hotel foyers and airport lounges the bridge between. Enlightened employers have realised the virtue of creating environments where people want to spend time.

They are both particularly eloquent on how banks have now gone down a blind alley by creating branches that look like mobile phone or betting shops.

“Banks are confused about how to name themselves. ‘Retail’ is entirely wrong: there should be a whole different mindset about service to a client, not a swift customer transaction. And if you think it is important that it is Scottish it should reflect that in the High Street.”

This is the dialogue Graven seeks with clients. “We didn’t have access to these guys when we started because they were scared of us,” says Kirkpatrick. “Now we are able to work at a more strategic level with corporations.”

When the revamped Kelvin Hall opens its doors later this year, their work there – including the public areas and café, a study centre for post-graduate Glasgow University students and archival storage – will be the latest contribution the practice makes to the fabric of life in the city Graven has helped redesign over the past 30 years. If 21st century Glasgow looks like a modern city, Hunter and Kirkpatrick are crucial to the reason it does so.

The Herald is media partner of Scotland's Festival of Architecture 2016