The retail bank is using Powercenter software from Informatica to feed more than one million transactions into its datawarehouse every day.
The customer data is then sent to marketing, finance and business support departments who analyse the data to help spot new business opportunities.
"ING Direct has grown so quickly in the UK and globally, that it is virtually impossible to set information-architecture requirements in stone," said Vincent Chatard, IT director at ING Direct UK.
"The [software's] flexibility enables changes to be implemented easily and efficiently within our datawarehouse environment, helping us maintain close relationships with our customers and to rapidly meet their needs."
Chatard said the Informatica software would pay for itself within two years. Last October ING said it had achieved a 400% return on investment from customer relationship management software used by its call centre staff.
It calculated that CRM software supplied by E.piphany had made it £2.8m in its first year.