So you have the perfect idea for your next SEO strategy, all you need is three or five days worth of time from the development and Q/A teams and it will become reality.  Once the change is implemented it'll improve efficiency / increase traffic immediately / increase traffic in the long run / all of the preceding (delete as applicable).  So now that it's all written up and placed on the development wiki, it's time to approach your boss, and get his buy-in.  Once that happens, the next step is to approach the CTO / CIO / Director of Development and see if any bandwidth is available to do the work.  Undoubtedly you'll hear that the workload is full with tasks for other areas of the business, and that you should wait until the next meeting of the developmental planning and prioritization meeting.

This meeting, common in the structured environments of medium - large organizations, sets the priorities for the development team for the next 4, 6, 8 weeks, or even further.  In fact, one large ERP company that I worked with had an annual prioritization meeting. Yes, that's right, annual... if you gave a bad / unconvincing speech, your department could be effectively shut out of the development process for a full calendar year. I knew of one department in this same ERP company that had had their development budget requests turned down for at least 3 years (this was where the company I worked for stepped up and developed the missing software, selling it to their customers as an add-on application. It worked out great for us until the customers got fed up with paying extra for functionality that was supposed to be in the core product, and lobbied the ERP firm to develop it or else... instead they ended up buying the company I worked for and giving our solution away as theirs).

Once you get into the prioritization meeting, having buy-in from as many players as possible is vital if you want to get development work done to get your strategy implemented.  This can be more of a challenge for a Search Engine Marketer, as not all of the players are necessarily aware of what it is that you actually do.  They may have some nebulous idea of what you do, but not necessarily know how you do it... "Yeah, she/he gets traffic to the sites, not really sure how, but it has something to do with robots or spiders or some such thing...".  This is why you have to prepare well in advance, making sure that you've been educating those in the organization that don't have direct, daily contact with you and the SEM effort in the 'mystical, magical arts' of SEM.  If you do that, then when the time comes to make your argument in the developmental prioritization meeting, you've a better chance of others understanding why what you want to do is important to the company, and why it should be prioritized ahead of that enhancement to a product that a potential customer has somewhat inquired about.  Of course, you then have the challenge of scope creep in tasks for other projects, and the specter re-prioritization mid-release, but that's a topic for another time...