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Why Small-Biz Expansion Depends on a Few High Fliers

But such initiatives miss an important middle step: support and guidance for the small businesses that are already up and running but need an extra boost of funding or mentorship to keep growing. The companies that want to expand should have be able to get ready access to the tools they need, whether it's legal advice, assistance with exports and imports or financing options.

The McKinsey paper also notes that it shouldn't be up to state and local governments alone to promote small-business growth. Larger, established businesses also can play an important role, by working with start-ups that have potential as suppliers and by mentoring young leaders. Too often, managers in large corporations look at entrepreneurs as potential competitors rather than potential partners. By looking the relationship in a different way -- what problem can this new, young company help me solve? -- large businesses can be part of the ecosystem that encourages growth.

"Growth" may be a generic, catch-all term. But there are very specific ways business leaders, economic-development boosters and local politicians can help make it happen for promising start-ups.