Microsoft and Amazon have announced that their Cortana-Alexa public preview is now available starting today. This means that Windows 10 users will be able to summon Amazon’s Alexa, while Echo speaker users will be able to summon Microsoft’s Cortana digital voice assistant.

The collaboration between Microsoft and Amazon was announced last year, but at the time, no information was given on when the Cortana-Alexa integration would be available to the public. Starting today, users will be able to access Alexa on Windows 10 devices by simply saying, “Cortana, open Alexa.” On Amazon’s Echo speakers, users will be able to access Microsoft’s assistant by saying, “Alexa, open Cortana.”

The Cortana-Alexa integration will be available across all of Amazon’s Echo speakers and PC devices running Windows 10. The new feature is also available on the Harman Kardon Invoke smart speaker, as confirmed by Amazon on its blog.

“With this public preview, we want users to engage with the experience and provide feedback so our teams can continue to improve the experience,” a Microsoft spokesperson told TechCrunch. “Our goal is to create a seamless integration and this is our first step towards achieving that goal.”

By having both of the digital assistants available across Echo speakers and Windows 10 devices, users will be able to take advantage of a lot of features. If users decide to summon Alexa on a Windows 10 PC for example, they will be able to ask Alexa to shop on Amazon. They would also have access to Alexa’s other skills, such as controlling smart home devices using voice commands.

On the Amazon Echo smart speakers, users will be able summon Cortana and ask her to read emails out loud or access their calendar schedule. Cortana is also capable of adding things to a to-do list. Microsoft and Amazon said that more features will be added in the near future.

“These early users will be asked to engage with the new features and offer input: what they like, what they don’t like, what features they use the most. The experience will get better and more precise as more people use it, through customer input and additional data to improve underlying algorithms,” Microsoft’s Jennifer Langston said on the company’s AI Blog.

“Some features such as streaming music and setting alarms are not yet available, but additional skills and devices will be integrated over time. Engineers will use feedback from the public preview to deepen the collaboration between Cortana and Alexa.”

Amazon is still leading the smart speaker race, but Microsoft is falling behind Apple and Google. So far, Microsoft has only made Cortana available on Windows 10 PCs, the Invoke smart speaker and smart thermostat GLAS. Cortana hasn’t been made available on more devices, according to The Verge. It’s possible that this collaboration with Amazon is part of Microsoft’s strategy to help broaden Cortana’s availability.