As a futures trader volume analysis is a key part of my research and my trades, the most important aspect of volume analysis we pay attention to is the Volume Profile. As well as the other methods we employ it forms a vital part of the research we do at Pivotfarm. It is something that is very popular amongst currency futures traders however it is something I very seldom see OTC Spot forex traders use, largely because forex is not centralized and thus there is no central exchange to collect this information, but mainly because most forex traders are completely unaware of it.
Never heard of Volume Profile? Most forex traders are unfamiliar with futures, in a nut shell currency futures (for e.g. 6E - Euro futures) are a derivative of the spot forex market, mirroring the movements of the underlying market. However the futures market is centrally/exchange traded with bodies like the Chicago Mercantile Exchange collecting this information and making it available to traders.

So what is this information? Most traders have come across the volume histogram at the bottom of your charts displaying volume at time i.e. how much volume was traded per time bar (1 min, 5 min etc). The Volume profile works in a similar way, however it is a sideways histogram displaying volume at price i.e. the actual volume traded throughout the day at that particular price point. This is a key distinction and what gives the volume profile its strength, you will see in a very visual way areas of price acceptance and rejection (high volume and low volume).
What is the value of this information to a trader? Areas of price acceptance/rejection are excellent tools to help you predict future price inflection points, they offer easy to find and generally high probability reversal areas. When analyzing the Index futures markets areas of high volume and low volume can act as support and resistance, however in my currency futures research I have tended to notice a greater favoring of low volume valleys in the currency futures.
Potential Issues? The futures market is a 24 hours market, however as the exchange has US based roots the greatest volume tends to be in the US session, this can have some impact due to the lower volume in the Asian/European session. Another thing to bare in mind is a small spread difference between the forex and futures market, usually 1-5 pips on the Euro, so anyone using the information to trade forex will need to make this small adjustment.
In the chart below key volume areas are highlighted, based upon this form of analysis alone we can expert Support/Resistance around the 1.3500s, 1.3530s, 1.3570s, 1.3600s, 1.3690s, 1.3770s, 1.3830s