Microsoft released on January 14 a preview version of Skype integration for Slack.
The preview enables teams on Slack to make Skype voice or video calls from within Slack.
Slack is an instant messaging-collaboration platform for teams.
Anyone on the Slack team will be able to start a Skype call from a computer by typing "/skype" into the Slack chat regardless of whether team members are using Slack on the Web, Windows, Mac, iOS or Android, according to a Microsoft blog post announcing the integration.
To join the Skype call, users need Skype on the desktop, in a Web browser or in the form of the various Skype mobile apps. A Skype account isn't required; users can participate as guests.
There's more information on the Skype integration for Slack product page. I've asked Microsoft for more as to the limitations on who can participate in the preview at this point and when the integration may be designated final.
Update: Availability of today's Skype-Slack integration is worldwide, according to a spokesperson. Microsoft isn't commenting as to when the integration will be designated "final." Official also won't say if and when Microsoft will release a Skype for Business-Slack integration offering, but will continue to monitor the needs of its users, the spokesperson said.
A bit of fine print worth noting from the product page:
"Standard Skype group calling limits apply. Get up to 10 participants on a group video call and 25 participants on a group voice call. Once the limit is reached, new participants won't be able to join. Guest joining is currently supported on web only. We'll be adding support for guest joining on mobile soon.
Coincidentally, just yesterday on Windows Weekly, we talked quite a bit about Skype (and mentioned Slack) as part of our Microsoft predictions for 2016.
Microsoft earlier this week announced its expansion plans for free Skype group-video calling. Free group video calling is coming to Android, iOS and Windows 10 Mobile "in the coming weeks," officials said.