In the April edition of "One Small Step for a Space Activist", Allen Sherzer & Tim Kyger write:   "Another problem is what are called 'wraps' (or sometimes    the 'center tax'). When work for a large program like    Freedom or Shuttle is performed at a NASA center, the    center skims off a portion which goes into what amounts    to a slush fund. This money is used to fund work the    center manager wants to fund. This sum is estimated to    be over a third of the funds allocated. Think about    that: Of the $30 billion cost of Freedom, fully $10    billion won't be spent on anything having anything    to do with Space Stations! Now, maybe that $10 billion    was wisely spent (and maybe it wasn't), but the work done    with it should stand on its own merits, not distorting    the cost of other projects. Congress has no idea of the    existense of these wraps; Congress has never heard the    term 'center tax'. They look at the Station they are    getting and the price they are paying and note that    it doesn't add up. They wonder this blissfully unaware    that a third of the money is going for something else."  My dear friends, your mixing fact and fiction here. A couple of weeks ago, when I first read this in your posting, I talked with one of the cost experts here in Space Station at Headquarters [if you wondering why I didn't post a response immediately, I do have a real job I'm supposed to be doing here at Headquarters, & digging up old 20 kHz data & looking into Sherzer/Kyger claims rates pretty low on the totem pole of priority. Also, I spent last weekend in Kansas City, at the National Science Teachers  Association conference, extolling the virtues of SSF to 15,000 science teachers.]  First off, yes, the concept of 'center tax', or 'wrap' does exist. If I recall the numbers correctly, the total 'tax' for the SSF program for this fiscal year is around $40 Million. This was computed by adding up the WP-1, WP-2, and WP-4 center 'taxes'. With the SSF budget for this fiscal year at $2.2 Billion, my calculater says the tax percentage is 04/2.2 = 1.8%  Over the life of the SSF program, using your figure of $30 billion for the cost of SSF, a tax at a 1.8% rate comes to $540 million. This is alot less than $10 billion, but I will concede it's still an appreciable amount of pocket change.  I should note that your estimate of the tax rate at 1/3 could be close to the actual rate. The tax is only charged on funds that are spent at the center (kind of like McDonalds at some states, where you do have to pay sales tax if you eat the food at the restaurant, but you don't if you get it take-out). For example, at WP-4, the vast bulk of the funds we receive go to the Rocketdyne Contract, and are *NOT* subject to the center tax (I don't have the numbers in front of me, but I'd guess at least 95% of the WP-4 funds go to Rocketdyne). So, you could be right about a tax rate of 1/3, but it's only applied to funds spent at the center, and not to the prime contracts.  This leads to the obvious question "What is the government doing with SSF funds that don't go to the prime contractors? (i.e. ok, WP-4 gets a slice of the $30 billion pie. A big portion of this slice goes to Rocketdyne. What happens to the balance of the funds, which aren't eaten up by the center tax?)"  At WP-4, we call these funds we spend in-house supporting development funds (as they are supporting the development work done by Rocketdyne). We have used these funds to setup our own testbed, to checkout the electrical power system architecture. Our testbed has a real life solar array field (left over from solar cell research research a few years back), with lead-acid car batteries (to simulate the Nickel-Hydrogen batteries on SSF), DC switchgear, DC-DC converter units, and simulated loads. Data from the testbed was used in a recent change evaluation involving concerns about the stability of the power system.  We have also used the supporting development money to purchase Nickel Hydrogen batteries, which are on life testing at both Lewis and the Crane Naval facility in Indiana. As a side point, 6 of the battery cells on test recently hit the four year life test milestone. 38 cells have completed 18,552 to 23,405 cycles (the on-orbit batteries go through 5,840 cycles per year).  As a final example, my 'home' division at Lewis used the supporting development funds to purchase personal computers and work stations, for performing system analyses (like modeling of the performance of the electrical power system, availability calculations using a Monte-Carlo simulation, setting up a  database with information on weight of the power system elements).  Finally, the money raised by the 'tax' does not all go into a 'slush fund.' At Lewis, the director does control a small discretionary fund. Each year, any individual at Lewis can submit a proposal to the director to get money from this fund to look at pretty much anything within the Lewis Charter.  Most of the tax, however, goes to fund the 'general' services at the Center, like the library, the  central computer services division, the Contractor  who removes the snow, etc. Thus, it is rather difficult to determine what percentage of the SSF budget doesn't go for SSF activities. To get an accurate figure, you would have to take the annual expenditure for the library (for example), and then divide by the amount of the library funds used to support SSF (which would be hard to compute by itself - how would you figure out what percentage of the bill for Aviation Week for 1 year is 'billable' to SSF, would you base it on the person-hours SSF employees spend reading AV-week versus the rest of the center personnel). You would then have to compare this estimate of the SSF portion of the library expense with the portion of the tax that goes to support the library. Who knows, maybe SSF overpays on the tax to run the library, but we underpay for snow removal? Talk about a burecratic nightmare!