While Microsoft Teams, the new collaborative tool coming with Office 365, evolves quickly, here is how to integrate Yammer with Teams to get the Yammer feed available.
Teams comes with lot of out of the box connectors – or you can also develop you own 
For this one, I will use the out of the box Yammer connector.
First you must have created a channel in your team – use the team contextual menu
For the purpose of this post I have create a new channel for Yammer
Then open the channel menu to add a connector
As you can see there is a lot of connector – from RSS to Twitter or Visual Studio, even Google Analytics or Facebook pages
Select Yammer (or any other connector you want to use, but as this post is about integrating Yammer, I’m choosing Yammer 
) and click Configure
You need to sign in to Yammer to be able to complete the configuration
Once authenticated you can view the account being used to connect to Yammer – I would recommend to use a dedicated account to connect to Yammer instead of using a user account
Then you can define the the Yammer group to grab the feed, the keyword you want to get notified… Keep in mind this must be a public Yammer group if you want to grab a specific Yammer group
You can define a specific group, keywords, or both.
Finally you have to configure the frequency to get the notification
Once completed the connector is displayed with the configuration associated with
You can update the connector configuration at any time
You will also get a notification to the channel to tell everyone a connector to Yammer has been setup with the configuration applied – in this example I’m looking for the keyword Office 365
For testing purpose (and this post), I then connect to Yammer to post a message with the keyword I’m monitoring
And the message is also posted to Team
And you can reply directly from Team back to the Yammer conversation but this will be only in Teams; your reply from Teams will not be published back to Yammer
If you need to change the connector configuration or delete it, just open the Connectors menu for the channel and then select Configured to get the list of configured connector(s) for this channel
Then click to Manage to update the configuration or delete the connector
And update the configuration or click Remove to delete it
