Under chairman and chief executive Sandy Weill, Citigroup has tried to pull off an intriguing business balancing act.

The largest US financial services company in terms of assets, Citigroup may be the most global banking company in the world, with a product breadth and geographic reach that knows no rival.

But Mr Weill, who likes to compare his far-flung business to a family, also has sought to maintain a local touch through dozens of acquisitions and alliances - such as last month's $12.5bn purchase of Mexican banking group Banacci.

Citigroup's worldwide securities services business - which includes custody, clearing services and depository receipts - is an example of this attempt to be both global and local at the same time.

The idea is to help clients who need local knowledge - about tax laws, securities regulation and the like - do business in more places and in more products.

"The clients' need are becoming more complex and that's because they are living in a global world. They are doing more cross-border investing. They are holding different kinds of instruments," says Sandra Jaffee, a Citibank executive vice-president and the group executive of Citibank worldwide securities services.

"We are the only custody provider in this particular arena that has a local presence in 52 markets around the world.

"That's 95 per cent of world market capitalisation. We use sub-agents in another 12, which brings us up to 99 per cent of the world's market capitalisation."

The advantage of having a local presence in so many places is that Citigroup can supply information to clients more quickly.

"We have delivered for our clients a client scorecard that can give the client at any point in the day their position on trades in every country where they are doing business with us," Ms Jaffee says.

"Before, you couldn't do it the same day. It took a little time to get it together."

Another recent development is CitiConnect for Securities, launched in April, which links Citibank's global clearing operations with the services of Salomon Smith Barney, Citigroup's investment banking unit.

"We have put together a module that will let universal banks do retail brokerage in terms of their trading and order routeing and settlement," she says.

Ms Jaffee says her business should expand from providing simple transactions processing to a more general role as a "sophisticated information provider," helping customers with outsourcing.

As proof of her point, Ms Jaffee says Citigroup's worldwide securities services business has boosted its revenues from big clients - contributing more than $5m in revenue a year - by 25 per cent in the last two years.

"We have a tremendous opportunity to do more with clients," she says.

"It's technological solutions with value-added information... It's about the intellectual capital you bring to the business."

Ms Jaffee says Citigroup has identified opportunities to grow its custody business both in the US and abroad.

Although based in the US, Citigroup's custody business is more significant overseas, a reflection of the old Citicorp's focus on banking operations outside the US.

By assets under custody, its US operations rank behind those of Bank of New York, State Street and JPMorgan Chase.

However, the 1998 merger between Citicorp and Travellers that created Citigroup brought with it a greater focus on US opportunities - including ones in custody.

In particular, Ms Jaffee says Citigroup wants to increase the business it does with US mutual funds.

"Citibank used to view itself as a global institution that happened to be headquartered in New York. Our focus was overseas," says Ms Jaffee, a former Peace Corps volunteer in Ethiopia. "We didn't do much business with US mutual funds."

As a result of this emphasis on its overseas reach, Citigroup is a market leader in Latin America, Europe and the Asia-Pacific.

Ms Jaffee says further expansion overseas will be made possible by changes in investment patterns, a notable example being the growth of equities in Europe. "We see phenomenal growth coming out of Europe," she says.

Overall, Citigroup provides services for investors and issuers with more than $4,000bn in assets under administration.