It is one of Europe's most divided regions, but there are some issues that have united the former Yugoslavia, including a deeply conservative outlook on sexuality and sex education.
But attitudes appear to be changing. Sex education classes were introduced to Croatian schools for the first time earlier this year, in the run-up to the country's accession to the European Union in July, and, from next month, classes will be piloted in parts of Serbia, too.
The move has proved controversial, however. Opposition from the Catholic Church led to Croatia's constitutional court ruling that the government should not have introduced the lessons in February because it had failed to properly consult parents.
The sex education curriculum has been suspended, but prime minister Zoran Milanovic is appealing against the judgment. He has also vowed to improve the quality of sex education so that it rivals the best in Europe.
Yet such difficulties have not deterred the regional government of Vojvodina, in the north of Serbia, from pushing ahead with plans to introduce the country's first sex edu- cation classes.
With Serbia still having some way to go before it is embraced by the EU, it has been able to introduce the lessons more gradually, with just 10 schools due to pilot the radical addition to the curriculum in September.
The Serbian provincial Ministry of Youth and Sport, which has instigated the sex education initiative, told TES that it had carefully laid the groundwork before putting its plan into action. Having consulted experts in areas including gynaecology and psychology, students will now have the opportunity to "learn about reproductive health", said Marinika Cobanu, provincial minister for sports and youth.
Classes will be delivered by teachers trained in medicine and psychology, who will work according to what Ms Cobanu described as a "British model" of sex education.
On the issue of parental consent she said: "As part of our research, we asked parents if they would like their children to attend sex education classes and more than 95 per cent said yes."
Vojvodina has long been regarded as Serbia's most liberal region, and it is uncertain how easy it will be for the rest of the country to follow suit in the introduction of sex education classes.
But the Vojvodina government believes it will not suffer any backlash from society, and has suggested that its experience in laying the groundwork could help in the national implementation of sex education.
"We believe that the Croatian scenario will not happen (here) because we underwent long and serious preparation that lasted 10 months and involved a series of studies, designing the programme and writing textbooks," Ms Cobanu said.
"In Croatia, it took them only two months to introduce sex education in schools and they did not predict the strength of the reaction from the Catholic Church, which is very influential in their society."
However, she added that the example from across the border was very welcome. "We were very pleased that the Croats first tried to introduce sex education in (their) schools," Ms Cobanu said. "They have provided support and assistance to us in a very positive way."