This special issue of Algorithmica contains expanded journal articles of selected papers from the eighth Latin American Theoretical INformatics conference (LATIN), which was held in the charming city of Buzios, Rio de Janeiro, Brazil, in April 2008. LATIN was launched in 1992 to foster the interaction between the Latin-American community and computer scientists around the world. The conference is now held every other year, and LATIN’08 was the eighth of a series, after Sao Paulo, Brazil (1992); Valparaiso, Chile (1995); Campinas, Brazil (1998); Punta del Este, Uruguay (2000); Cancun, Mexico (2002); Buenos Aires, Argentina (2004); and Valdivia, Chile (2006). In the past two decades, LATIN has established itself as a theoretical computer science conference of the highest standards, and this special issue reflects this fact. LATIN’08 had more than 120 participants among students and researchers from academia and industry. Its conference proceedings were published, as with all past LATINs, by Springer-Verlag in the Lecture Notes in Computer Science series. There were sixty six papers presented in LATIN’08, and Volume 4957 of the LNCS series is devoted to them. This special issue includes the following expanded papers: • Origami Embedding of Piecewise-Linear Two-Manifolds. Marshall Bern and Barry Hayes • On Dissemination Thresholds in Regular and Irregular Graph Classes. Ivan Rapaport, Karol Suchan, Ioan Todinca and Jacques Verstraete • Quantum Property Testing of Group Solvability. Yoshifumi Inui and Francois Le Gall