title: Capacity planning when using Kanban-base/Lean development
body: <p>We are currently using Scrum to help develop a set of software libraries in C++ and C#.  The nature of the domain is such that we need to be pretty reactive to changing requirements - so much so that sprint-planning often ends up being a waste of time due to the high level of emergent work.  I'm thinking it's time to switch to a lean (kanban) development model instead of Scrum since this has worked reasonably well for us the past. </p>
  
  <p>Also on my mind though, is that I'd like to be able to make a case to my managers that my team is understaffed.  I'm unclear on how to do this effectively since lean methodologies espouse very minimal time spent on task estimation.  I should be encouraging our customers (and my managers) to focus on priority of work rather than how long each feature will take.  Thing is, we still have a hard deadline to hit and they want to know we can hit it.  In order to commit, I feel the need to measure things and calculate the staff I reckon I need!</p>
  
  <p>The problem is that I don't know how I can make an argument for more staff if my team is using a process that focuses on prioritisation - I'd need to estimate all the work we're expected to get done and then present the numbers to demonstrate "we'll need X more people".</p>
  
  <p>In essence I suppose I'm asking whether anyone has any good tips for measuring, and making a case for changes in, team capacity when you have adopted a lean, agile process?</p>