Dear colleagues, The Complex Engineering Systems Institute (ISCI) invites you to submit an abstract for LAND-TRANSLOG IV, a unique workshop that has been held in Chile with great success since 2011, merging the previously separate workshops LAND and TRANSLOG. The workshop will take place from December 8 to December 12, 2019 at a new great location; the Dreams Valdivia hotel in the south of Chile. We are glad to announce our keynote speakers: Michel Gendreau, Stefan Nickel, Mikael Rönnqvist, Francisco Saldanha Da Gama and Cristián Cortés. We anticipate a variety of contributions. *Please send your abstract by September 30 (new deadline).* Acceptance notifications will be sent as soon as possible. Important: If required for travel fund purposes, we will happily provide express acceptance of papers upon reception of abstracts. For further information please visit the following link: http://land-translog.cl/19/en/inicio Sincerely yours, Eduardo Álvarez, Cristián Cortés, Vladimir Marianov, Andrés Weintraub.