Many application designs are built or prototyped in a very small scale – then have difficulty deploying into the “real world”. There is a temptation to “get the product out the door”, leading to implementation decisions that are fundamentally bad for a high-volume, or even just multiuser, environment. Scalability concerns used to be the preserve of banks, telcos or online service providers. With the change to cloud computing, and the increasingly global 24x7x365 nature of the information technology world, the lessons of reliability, scalability and availability are increasingly relevant to the designers, builders or customers of applications delivered online. In the two books showcased at scalability.com, Marty Abbott and Michael Fisher examine this are from two different points of view. “The Art of Scalability” introduces concepts of organisation, process, risk management and leadership alongside technology and architecture as key elements of a scalable solution design. “Scalability Rules – 50 Principles for Scaling Web Sites” takes a more technology led view of the challenges, bringing out many lessons learned from high volume environments like AOL, Paypal and eBay. These books represent an excellent introduction to the concepts of high availability design, scalable in sensible (and affordable!) increments, and will help the reader understand some of the challenges of volume and scale which may not always be apparent at the proof-of-concept or prototyping stage.