After all of the coverage of the EU referendum, one thing has become abundantly clear to many investors. Investing in geographically diversified companies is a must. Certainly, the world is becoming more globalised and what happens in one region can easily impact the macroeconomic outlook of another region on the other side of the world. However, diversification between different economies can still reduce risk and still provide excellent reward opportunities.

One company that offers such potential is BP (LSE: BP). Its asset base is geographically well-diversified and so it offers a relatively low geographical risk. Of course, on the flip side BP is highly dependent on the price of oil and so is risky from that perspective. But with its shares offering a wide margin of safety and very promising growth forecasts, now seems to be an excellent time to buy a slice of the business for the long term.

For example, following the oil price rise from its 2016 lows to around $50 per barrel, BP’s anticipated profitability has risen significantly for the 2017 financial year. It’s due to increase its bottom line by 115% as the effects of rising oil price and greater efficiencies are expected to take hold. And with there being scope for further improvements in both of these areas, BP’s price-to-earnings growth (PEG) ratio of 0.1 indicates that it’s a top-notch growth play trading on a low valuation.

Non-UK growth

Also offering a geographically well-diversified growth outlook is Alliance Pharma (LSE: APH). Its exposure to international markets was boosted by the recent acquisition of the healthcare products business from Sinclair Pharma. Crucially, this increases Alliance Pharma’s exposure to non-UK markets, with over 50% of its business now being conducted outside of the UK.

Clearly, Alliance Pharma has an excellent track record of making the right acquisitions, both in terms of the licenses it acquires and the price it pays for them. The healthcare products transaction appears to be a logical one and with Alliance Pharma forecast to increase its bottom line by 8% this year and by a further 9% next year, its outlook is very positive. Its shares currently trade on a PEG ratio of just 1.2, which indicates that now is a great time to buy them for the long term.

Low geographic risk

Meanwhile, Next Fifteen (LSE: NFC) also offers an excellent international growth profile. The advertising and PR specialist operates across the globe and has a particular focus on hi-tech opportunities in the US. This provides it with relatively low geographic risk and with the company having made multiple acquisitions, it has developed a portfolio of 17 different businesses that again help to de-risk the opportunity on offer to investors.

With Next Fifteen expected to increase its bottom line by 9% this year and by a further 10% next year, it offers above average growth prospects. And due to Next Fifteen having a PEG ratio of 1.2, it does so at what is a relatively appealing valuation. Therefore, with a diverse geographical exposure and a proven acquisition model, Next Fifteen appears to be a star buy for the long term.

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Peter Stephens owns shares of Alliance Pharma, BP, and Next Fifteen Communications. The Motley Fool UK has recommended BP. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.