It's difficult to lock down the absolute best stocks to buy for any year - but 2020 could be particularly challenging.

For one, 2019's run-up has lifted stocks to sky-high prices only seen a handful of times in history. Also, the global economy is starting the year at a potential inflection point - growth has been weakening for months, but signals of a turnaround are starting to pop up. And the 2020 presidential cycle is almost certain to cause headaches for a number of politics-sensitive sectors.

The year ahead could be every bit as volatile as 2019, if not moreso. Thus, the best stocks for 2020 will need to have not just decent-to-robust growth prospects, but a little durability too. That's quite the needle to thread ... but several companies do fit that bill.

Here are the 20 best stocks to buy for 2020, rain or shine. A few of these possess typical defensive characteristics such as recession-resistant businesses and/or high dividend yields. A few possess qualities that could protect them from 2020-specific dangers, such as trade turbulence or the upcoming presidential elections. But all of them merit a place in most stock portfolios in the coming year.

AstraZeneca

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AstraZeneca (AZN, $47.98) is a U.K.-based biopharmaceutical giant with treatments in oncology, cardiovascular, renal, respiratory and several other fields. It boasts a few dozen approved drugs, as well as a deep pipeline of 164 trial-stage treatments, including nine new molecular entities in late-stage trials.

Among its premier products are several cancer treatments, including Tagrisso (non-small cell lung), Imfinzi (bladder) and Lynparza (ovarian, breast and prostate). Tagrisso, which is approved in 87 countries, is AstraZeneca's best-selling drug, racking up $2.3 billion in sales across the first nine months of 2019 - that represents 82% year-over-year growth, and 13% of the company's year-to-date revenues. Better still, in the third quarter, Tagrisso and several other drugs had positive readouts in late-stage trials.

Despite all this success, Cowen analyst Steve Scala writes that the company's product momentum isn't being properly recognized. In December, he reiterated his Outperform rating (equivalent of Buy) and raised his price target to $55 per share from $48 previously, or roughly 15% upside potential. He also thinks that low U.S. exposure should insulate the stock from the upcoming presidential election cycle - a feature that makes AZN stand out among the best stocks to buy for 2020.

One more thing to like: Strong growth in China. The company's $3.7 billion in revenues through 2019's first nine months was 30% better than the same period in 2018. AstraZeneca's position in China and other emerging markets should serve it well in the year ahead.

Bright Horizons Family Solutions

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