Almost 3.7 million housing units are unused, either vacant or closed. According to the 2006 census, the total number of unused units in urban areas in Egypt reached 4.58 million units, of which 1.18 million were closed and 3.40 million were vacant. Due to the lack of detailed breakdown by unit use in the preliminary census results made available by CAPMAS, it was estimated that 3.72 million or 81.3% of these 4.58 million unused units are for housing use, while the remaining 18.7% are for work use (commercial and office space in mixed-use buildings, housing units informally converted into office space, etc.). 1 The scale of vacant urban housing units, much more serious than in other emerging markets, is a specific and puzzling phenomenon of the Egyptian housing market. One explanation is that the sustained rapid appreciation in value over the past 25 years or so and the lack of alternative investment mechanisms until quite recently meant that housing and real estate have consistently served as inflation-proof savings and investment mechanisms, without the need for the rental yield.  The idea of renting was even less attractive due to the imposition of rent control until 1996. Even now, the continued perception of uncertainty about the enforceability of the new rental law makes many owners hesitant to put their unoccupied units to rent. Poor targeting of government-subsidized units, as well as the most unattractive locations in New Towns, have also further exacerbated the problem. An estimated 42% of the housing stock is frozen under rent control. Since the passage of Law No. 4 of 1996 freed the rental market for newly built and then-vacant units, but grandfathered existing rent-controlled units for the duration of the contract, the rental market is showing signs of much dynamism. This greatly constrains residential mobility, locks a large proportion of units out of the market, causes a lack of stock maintenance, and distorts the overall housing market.