diff --git a/05-osm-usage.md b/05-osm-usage.md
index 52353ec2351198c5a8949c7c3e3fcc456cbf98bc..bafd958bc2a775760ed7a4385400b0b4229fbb55 100644
--- a/05-osm-usage.md
+++ b/05-osm-usage.md
@@ -633,6 +633,17 @@ An existing persistent volume could be passed as an instantiation parameter by i
 
 Where the `name` of the `persistent-storage` is the one in the descriptor, and the `vim-volume-id` is the ID of volume in Openstack to be used (instead of being created).
 
+### Using existing flavors (OpenStack only)
+
+Typically, OSM creates the flavors needed by the VDUs, which are specified by the `virtual-compute-desc` parameter in the VNFD. In some cases, flavors must contain a complex EPA configuration that is not supported by descriptors, so they need to be created manually in the VIM beforehand.
+
+An existing flavor can be used by passing it's ID to `vim-flavor-id` at the VDU level. The following example shows the syntax:
+
+```yaml
+--config '{vnf: [ {member-vnf-index: "vnf", vdu: [ {id: hackfest_basic-VM, vim-flavor-id: "O1.medium" } ] } ] }'
+```
+
+
 ## Understanding Day-1 and Day-2 Operations
 
 VNF configuration is done in three "days":