Saudi Arabia, the world's largest oil producer, is transitioning from an oil-based economy to one based on knowledge, as part of a national science strategy through 2030. Significant investments have enabled the country to establish high-tech universities and advanced research laboratories. The Nature Index 2016 supplement highlights Saudi Arabia's growing scientific output, which has surpassed other Arab states and placed it second in Western Asia. This growth is driven by five key institutions, which have collaborated with 89 countries in 2015, contributing to the country's rise in the index. The United States and China remain the main partners in scientific collaborations with Saudi Arabia. Leading institutions like KAUST and KAU are driving international collaborations through different approaches. While most Saudi institutions have smaller contributions to collaborations compared to their international counterparts, the Saudi government has launched a scholarship program to foster homegrown talent. Saudi Arabia has the fastest growing weighted fractional count (WFC) in the Middle East in 2015, driven by a strong focus on chemistry, which accounts for two-thirds of its science output in the Nature Index. The country's international standing has risen significantly since 2012, and it aims to compete with leading Asian nations. The Nature Index supplement acknowledges financial support from KACST and is produced by Nature. The supplement includes various sections on Saudi Arabia's scientific growth, institutional rankings, and an explanation of the index metrics. The cover image shows Riyadh's skyline with the Kingdom and Al Faisaliyah centres. The editorial team and production staff are listed, along with contact information for advertising and feedback. Copyright 2016 Nature Publishing Group.Saudi Arabia, the world's largest oil producer, is transitioning from an oil-based economy to one based on knowledge, as part of a national science strategy through 2030. Significant investments have enabled the country to establish high-tech universities and advanced research laboratories. The Nature Index 2016 supplement highlights Saudi Arabia's growing scientific output, which has surpassed other Arab states and placed it second in Western Asia. This growth is driven by five key institutions, which have collaborated with 89 countries in 2015, contributing to the country's rise in the index. The United States and China remain the main partners in scientific collaborations with Saudi Arabia. Leading institutions like KAUST and KAU are driving international collaborations through different approaches. While most Saudi institutions have smaller contributions to collaborations compared to their international counterparts, the Saudi government has launched a scholarship program to foster homegrown talent. Saudi Arabia has the fastest growing weighted fractional count (WFC) in the Middle East in 2015, driven by a strong focus on chemistry, which accounts for two-thirds of its science output in the Nature Index. The country's international standing has risen significantly since 2012, and it aims to compete with leading Asian nations. The Nature Index supplement acknowledges financial support from KACST and is produced by Nature. The supplement includes various sections on Saudi Arabia's scientific growth, institutional rankings, and an explanation of the index metrics. The cover image shows Riyadh's skyline with the Kingdom and Al Faisaliyah centres. The editorial team and production staff are listed, along with contact information for advertising and feedback. Copyright 2016 Nature Publishing Group.