While her husband Prince Felipe was in South America for the inauguration of Uruguay's new president, Letizia touched down in Berlin to be guest of honour at a prize-giving ceremony for medical research.
Invited by Eva Luise Kohler, wife of German President Horst Kohler, the princess first attended a lunch for award-winners and other ceremony guests hosted by the couple's foundation in the Bellevue presidential palace.
Wearing a blue dress by her top designer Felipe Varela, she then travelled across town to the main event, the Eva Luise and Horst Kohler Foundation's award ceremony for research into rare diseases, where she gave a speech.
The princess is a known supporter of rare disease research. In 2009 she presided at the prize-giving for the Spanish Federation of Rare Diseases and has received many different associated organisations at the Zarzuela Palace.
Last March she met Eva and Horst in Madrid, where they spoke to her about the work of their foundation at a dinner hosted by the king and queen.