diff --git a/audit/format_json.go b/audit/format_json.go
new file mode 100644
index 0000000000..6bfbb3624f
--- /dev/null
+++ b/audit/format_json.go
@@ -0,0 +1,126 @@
+package audit
+
+import (
+	"encoding/json"
+	"io"
+
+	"github.com/hashicorp/vault/logical"
+)
+
+// FormatJSON is a Formatter implementation that structuteres data into
+// a JSON format.
+type FormatJSON struct{}
+
+func (f *FormatJSON) FormatRequest(
+	w io.Writer,
+	auth *logical.Auth, req *logical.Request) error {
+	// If auth is nil, make an empty one
+	if auth == nil {
+		auth = new(logical.Auth)
+	}
+
+	// Encode!
+	enc := json.NewEncoder(w)
+	return enc.Encode(&JSONRequestEntry{
+		Auth: JSONAuth{
+			Policies: auth.Policies,
+			Metadata: auth.Metadata,
+		},
+
+		Request: JSONRequest{
+			Operation: req.Operation,
+			Path:      req.Path,
+			Data:      req.Data,
+		},
+	})
+}
+
+func (f *FormatJSON) FormatResponse(
+	w io.Writer,
+	auth *logical.Auth,
+	req *logical.Request,
+	resp *logical.Response,
+	err error) error {
+	// If things are nil, make empty to avoid panics
+	if auth == nil {
+		auth = new(logical.Auth)
+	}
+	if resp == nil {
+		resp = new(logical.Response)
+	}
+
+	var respAuth JSONAuth
+	if resp.Auth != nil {
+		respAuth = JSONAuth{
+			ClientToken: resp.Auth.ClientToken,
+			Policies:    resp.Auth.Policies,
+			Metadata:    resp.Auth.Metadata,
+		}
+	}
+
+	var respSecret JSONSecret
+	if resp.Secret != nil {
+		respSecret = JSONSecret{
+			LeaseID: resp.Secret.LeaseID,
+		}
+	}
+
+	// Encode!
+	enc := json.NewEncoder(w)
+	return enc.Encode(&JSONResponseEntry{
+		Auth: JSONAuth{
+			Policies: auth.Policies,
+			Metadata: auth.Metadata,
+		},
+
+		Request: JSONRequest{
+			Operation: req.Operation,
+			Path:      req.Path,
+			Data:      req.Data,
+		},
+
+		Response: JSONResponse{
+			Auth:     respAuth,
+			Secret:   respSecret,
+			Data:     resp.Data,
+			Redirect: resp.Redirect,
+		},
+	})
+}
+
+// JSONRequest is the structure of a request audit log entry in JSON.
+type JSONRequestEntry struct {
+	Auth    JSONAuth    `json:"auth"`
+	Request JSONRequest `json:"request"`
+}
+
+// JSONResponseEntry is the structure of a response audit log entry in JSON.
+type JSONResponseEntry struct {
+	Error    string       `json:"error"`
+	Auth     JSONAuth     `json:"auth"`
+	Request  JSONRequest  `json:"request"`
+	Response JSONResponse `json:"request"`
+}
+
+type JSONRequest struct {
+	Operation logical.Operation      `json:"operation"`
+	Path      string                 `json:"path"`
+	Data      map[string]interface{} `json:"data"`
+}
+
+type JSONResponse struct {
+	Auth     JSONAuth               `json:"auth,omitempty"`
+	Secret   JSONSecret             `json:"secret,emitempty"`
+	Data     map[string]interface{} `json:"data"`
+	Redirect string                 `json:"redirect"`
+}
+
+type JSONAuth struct {
+	ClientToken string            `json:"string,omitempty"`
+	Policies    []string          `json:"policies"`
+	Metadata    map[string]string `json:"metadata"`
+}
+
+type JSONSecret struct {
+	LeaseID string `json:"lease_id"`
+}
diff --git a/audit/format_json_test.go b/audit/format_json_test.go
new file mode 100644
index 0000000000..2fca3a900b
--- /dev/null
+++ b/audit/format_json_test.go
@@ -0,0 +1,42 @@
+package audit
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/hashicorp/vault/logical"
+)
+
+func TestFormatJSON_formatRequest(t *testing.T) {
+	cases := map[string]struct {
+		Auth   *logical.Auth
+		Req    *logical.Request
+		Result string
+	}{
+		"auth, request": {
+			&logical.Auth{ClientToken: "foo", Policies: []string{"root"}},
+			&logical.Request{
+				Operation: logical.WriteOperation,
+				Path:      "/foo",
+			},
+			testFormatJSONReqBasicStr,
+		},
+	}
+
+	for name, tc := range cases {
+		var buf bytes.Buffer
+		var format FormatJSON
+		if err := format.FormatRequest(&buf, tc.Auth, tc.Req); err != nil {
+			t.Fatalf("bad: %s\nerr: %s", name, err)
+		}
+
+		if buf.String() != tc.Result {
+			t.Fatalf(
+				"bad: %s\nResult:\n\n%s\n\nExpected:\n\n%s",
+				name, buf.String(), tc.Result)
+		}
+	}
+}
+
+const testFormatJSONReqBasicStr = `{"auth":{"policies":["root"],"metadata":null},"request":{"operation":"write","path":"/foo","data":null}}
+`
diff --git a/audit/formatter.go b/audit/formatter.go
new file mode 100644
index 0000000000..c1f5597f1d
--- /dev/null
+++ b/audit/formatter.go
@@ -0,0 +1,15 @@
+package audit
+
+import (
+	"io"
+
+	"github.com/hashicorp/vault/logical"
+)
+
+// Formatter is an interface that is responsible for formating a
+// request/response into some format. Formatters write their output
+// to an io.Writer.
+type Formatter interface {
+	FormatRequest(io.Writer, *logical.Auth, *logical.Request) error
+	FormatResponse(io.Writer, *logical.Auth, *logical.Request, *logical.Response, error) error
+}