DHL’s Paperless Trade service allows you to electronically transmit Commercial and Proforma Invoices, eliminating the need to print and physically attach them to your shipments.
To enable this, you will need to discuss with your account manager in DHL.
Please see more information below.
http://www.dhl.co.uk/content/dam/downloads/gb/express/shipping/paperless_trade/paperless_trade_brochure.pdf