SOA - Service Orientation Applied

Contrary to the notion of big systems, monoliths or all in one-systems, SOA proposes a modular sourcing approach. Instead of making investment on one big technology or one big product and committed to that for years to come, enterprises are contemplating to adopt modular solutions with smaller investments, with faster time to market and eventually replaceable with latest technologies with out huge reinvestments. Success stories related to Software as a Service (SaaS) providers such as salesforce.com or Amazon marketplace, shows the early signs of such flexible solutions. In addition to leveraging external providers, enterprise IT organizations are expanding the meaning of [internal] ‘shared services’ from conventional candidates such as finance and HR systems to essential [common] capabilities of  identity and access management, content management, document generation and so on.
  
It might be the same reason of ‘flattening’ that makes the ERP product vendors to invest on SOA e.g. SAP’s ESA or Oracle’s Fusion. It makes the ERP solutions much more modular, loosely coupled between various process implementations, easily customizable, incrementally adoptable and easy to integrate in a best of breed scenario. It is worth mentioning, especially considering ERP vendors’ such as SAP’s steer towards middle market where incremental adoption can be very attractive.