A received reply email document enables some action to be effectuated using data included in the email document responsive to field identifiers associated with the data and corresponding to fields of metadata. The associated field identifiers that correspond to known fields of the metadata provide some expectation as to the semantic meaning and/or syntactic constraints of the data to which the field identifiers are associated. In a described implementation, an actionable email documents module creates an email document having blocks that are mapped to fields of metadata. The email document is transmitted to one or more recipients. Each recipient adds data to the blocks so that the data becomes mapped to the fields of the metadata. The recipients return a reply email document having the field-mapped data. Upon receipt, the module can effectuate some action using the field-mapped data responsive to the mappings.