Goede tijden, slechte tijden (Dutch pronunciation: [ˈɣudə ˈtɛidə(n) ˈslɛxtə ˈtɛidə(n)], lit. 'Good times, bad times'), also known as GTST or simply Goede tijden, is the longest-running Dutch soap opera, which began on 1 October 1990 on RTL4. The programme was the first daily (every workday) soap in the Netherlands and Europe. The soap is produced by Joop van den Ende and to date over 6,900 episodes have been broadcast. It was initially based on the Australian soap The Restless Years, however it switched to original scripts during the third season and onwards. GTST is broadcast Monday to Friday at 20:00, and became available on demand via streaming platform Videoland from 2015.

At its peak, the show drew around 1.5 million viewers daily, in a country of just over 15 million people at the time. In 2022 the show was still watched by over 1 million people, with around 800.000 watching it on TV and an additional 300.000 viewers on Videoland. In 2024 it nearly reached a million viewers. After 33 years, it remains the highest-rated soap opera in the Netherlands.

The soap mainly revolves around the lives of the families Alberts, Sanders, De Jong, Van Houten and Bouwhuis. It is set in the fictional town of Meerdijk. As in any other soap, marriage, divorce, kidnapping and business are a few of the ingredients of GTST, although in recent years GTST has become known for writing and producing more controversial storylines. GTST is also known for having a summer break each year, ending a season sometime in June with a cliffhanger, only to resume three months later in September. Although the early cliffhangers often revolved around family drama, later cliffhangers have often revolved around disasters and unexpected twists.

Many former actors who once were part of the cast are now well known in the Netherlands and Europe, including Katja Schuurman, Reinout Oerlemans, Georgina Verbaan, Antonie Kamerling, Erik de Vogel, Caroline De Bruijn, Bartho Braat, Inge Schrama and Melissa Drost.

In 2014, there was a gay marriage in the soap opera; this was the first time this happened in a Dutch TV show.

In 2016, the show gained a spin-off called Nieuwe Tijden (English: New Times), which follows some of the younger characters from GTST and some new characters as they go off to college. Nieuwe Tijden was cancelled in 2018.