SLAs seem to have the effect of dramatically changing the culture of the team that is now measured by the SLA.<p>I remember two times when my managers announced an SLA.
First time was "Every priority 1 ticket has to be answered within 24 hours".
Before the SLA we were a cheerful and overworked IT team, doing our best to handle all tickets within reasonable times and with our best quality responses.
Afterwards - We started negotiating priorities, replying "investigating" within 24 hours to make sure management doesn't get on our case, and we had lots of not-so-funny jokes about announcing "love every 38 hours" SLAs to our spouses.<p>The second time they actually went as far as saying "This SLA is between marketing, sales and the customer. You don't need to worry about it. Just keep on doing what you always did."<p>They had to say that, because with our current equipment and processes, offering 99.9% availability to our customers was impossible. Our real availability was an average of 99.5% with some services as low as 97%. Not because we were horrible IT - but because of trade-off decisions we reached in the past together with our management.<p>It didn't help much. Because we didn't trust management not to start holding us to those SLAs at a random moment. Which they did.<p>Again, from a team that did their best to keep servers up, we became expert negotiators of which downtimes "count" and which don't. Also, we because very defensive: "We can't risk upgrading this month, we were already down 13 minutes."<p>I understand the need to sell to corporates, but I would be very very careful communicating SLAs to my team.