Robert Half International (RHI 0.83%) reported a solid first quarter. Total revenue increased 5.8%, to $1.1 billion, and earnings per share increased 13%, to $0.45, besting analyst estimates by $0.01. This marked the 16th consecutive quarter of double-digit earnings-per-share growth. Below are my four key takeaways from the quarter.

1. Strong sales growth at home and abroad
Sales growth was stronger both domestically and internationally. Keeping in line with recent trends, domestic results were better. Staffing revenue in the United States grew 6.4%. Weak employment in Europe has been a consistent drag on growth -- international staffing revenue fell every quarter in 2013. But we may have hit a bottom, as international revenue didn't fall this quarter. It actually increased, though only by a minuscule amount -- 0.1%.

2. Profitability continues to improve
The big story at Robert Half isn't sales growth, it's about improving profitability. During the lows of the Great Recession, the company's profits fell dramatically. In 2009, the company reported 2.2% operating margins. Since then, the company has expanded margins every year. In this quarter, operating margins increased 9.4%. That's why the company has four years of double-digit growth in profits.

3. The balance sheet remains rock solid
The company has $268 million in cash and only $1.3 million in debt. And the business model doesn't require large investments in physical capital to fund growth. This allows the company to pay out excess cash to shareholders. During the quarter, the company repurchased 825,000 shares. The diluted share count today is 1.6% lower than a year ago. And the company pays a 1.7% dividend.

4. Management is predicting a brighter future
According to CEO Harold Messmer, demand for staffing services is strong, and it's actually been accelerating in the past few months. Even Europe, a perpetual weak spot, is improving. Here's what he said on the earnings call:

Demand for our professional staffing services and Protiviti consulting solutions remained solid during the first quarter, with growth rates accelerating in March and so far in April. We were also pleased to see higher staffing demand outside the United States, including Europe.

And, the long-term trend toward temporary workers seems to be playing out. Businesses are increasing employing temporary staff, especially domestically. Here's how Messmer describes the trend:

The first quarter saw the number of temporary workers as a percentage of total U.S. employment exceed the all-time high established in 2000. More and more businesses appreciate the value of interim staff to better manage variable workloads and specialized project demands.

Foolish Bottom Line
Robert Half continues to report respectable, if unspectacular results. Its profitability continues to increase, and earnings per share continue to march upward at double-digit rates. During the past year, the stock has generated a total return of 33% -- nicely outpacing the S&P 500, which returned 22%. Of course, the future of the company is heavily dependent on employment levels, but the trends seem positive.