Livestreaming is so easy and so accessible, to organizations as well as the people they serve. If your organization has public meetings and events, they should be livestreamed. If your organization has VIPs, they should be given access to VIP-only content via livestream. Livestreaming, unlike other video content, doesn't take editing time, batching time, or even hard drive space if you don't want it to.
A livestream kit can be as cheap as your laptop's built-in mic and camera, an app on your smartphone, or a $20 USB mic and a $17 webcam. Or as expensive as a $15,000 TriCaster. The difference in cost can be attributed to quality, reliability, and branding.
I strongly suggest that professional organizations avoid anyone who will put commercials in their stream, or who will insert them after the fact, when a customer/member/donor is watching a replay of the feed. It may be okay for individuals using the service to promote their band, or show the baby to the grandparents, but this may hurt a serious organization.
A lot of streaming services offer free versions, but charge money to remove commercials from replay, and substitute your branding for theirs when viewers log on. Ustream, for example, puts ads in their free subscribers streams. Although Pro subscribers have no ads. The minimum charge for a pro account is $99 per month.
YouTube Live is a good alternative, although not all YouTube users qualify for the service. A person has to have a spotless YouTube record, have verified their account via SMS, and they sometimes still won't grant access. Livestream.com promises no ads, but doesn't allow users to embed on outside sites at any level under the $399/month Premium, and demands viewers be livestream.com members to watch streams from free accounts.
Every organization is different, and there are a lot of livestreaming options, each with their own set of features, costs, and drawbacks. It's important that you look and find the company that most matches with your own style and needs.
Remember to test, test, test any set-up you have before the main event, but after that, livestream your heart out. Get moment-to-moment feedback from your community, engage with a larger audience, and bring new people into the fold. Most importantly, have fun and reach out.