Running Graphene tests and use parallelStream method makes test fail with java.lang.IllegalStateException: The Graphene runtime isn't initialized. Exception. ------------------------------------------------------------------------------------------------------------------------------------------------------------- Key: ARQGRA-461 URL: https://issues.jboss.org/browse/ARQGRA-461 Project: Arquillian Graphene Issue Type: Bug Reporter: Alex Soto Priority: Minor Labels: java8,, threads Running Graphene tests and use parallelStream method makes test fail with java.lang.IllegalStateException: The Graphene runtime isn't initialized. Exception. Basically the problem is when you want to get information about tables. You can iterate over elements in a foreach fashion, but you can also use new Java 8 stream API. This works: ession.findElements(xpath("//table/tbody/tr/td/span[@class='title']")).stream().map(WebElement::getText).collect(Collectors.toList()); But if table is big you will try to improve parsing speed by adding parallelSteam (session.findElements(xpath("//table/tbody/tr/td/span[@class='title']")).parallelStream().map(WebElement::getText).collect(Collectors.toList());) And in this case an exception is thrown. Internally parallelStream uses a pool of threads so probably Graphene instance is tight to thread of test case, so the threads used by parallelStream does not contains a valid instance of Graphene. Of course this is not blocking nor a big problem in the sense that you can use stream() without any problem, and moreover Java 8 is not spread yet, but it may be a problem in the future.