diff --git a/src/engine/mod.rs b/src/engine/mod.rs
index 1fc2777..288343c 100644
--- a/src/engine/mod.rs
+++ b/src/engine/mod.rs
@@ -3,7 +3,7 @@ pub mod service;
 pub mod state;
 
 use crate::proto::{NetAction, NetEvent};
-use db::Db;
+use db::{Db, RegError};
 use service::{Sender, Service, ServiceCtx};
 use state::Network;
 
@@ -46,10 +46,35 @@ impl Engine {
                 Vec::new()
             }
             NetEvent::Privmsg { from, to, text } => self.dispatch(&from, &to, &text),
+            NetEvent::AccountRequest { reqid, kind, account, p2, p3, .. } => {
+                self.account_request(reqid, kind, account, p2, p3)
+            }
             _ => Vec::new(),
         }
     }
 
+    // Authority side of the IRCv3 account-registration relay: create the account
+    // (same store as classic NickServ REGISTER) and answer the requesting ircd.
+    fn account_request(&mut self, reqid: String, kind: String, account: String, p2: String, p3: String) -> Vec<NetAction> {
+        if !kind.eq_ignore_ascii_case("REGISTER") {
+            return Vec::new(); // VERIFY / RESEND / STATUS: later
+        }
+        let email = if p2.is_empty() || p2 == "*" { None } else { Some(p2) };
+        let (status, code, message) = match self.db.register(&account, &p3, email) {
+            Ok(()) => ("success", "*", "Account registered."),
+            Err(RegError::Exists) => ("error", "ACCOUNT_EXISTS", "That account name is already registered."),
+            Err(RegError::Internal) => ("error", "TEMPORARILY_UNAVAILABLE", "Registration is unavailable, try again later."),
+        };
+        vec![NetAction::AccountResponse {
+            reqid,
+            kind,
+            account,
+            status: status.to_string(),
+            code: code.to_string(),
+            message: message.to_string(),
+        }]
+    }
+
     // Route a PRIVMSG addressed to a service (by uid or nick) into that service,
     // handing it the sender's resolved nick and the account store.
     fn dispatch(&mut self, from: &str, to: &str, text: &str) -> Vec<NetAction> {
diff --git a/src/proto/inspircd.rs b/src/proto/inspircd.rs
index f2f4f04..166a202 100644
--- a/src/proto/inspircd.rs
+++ b/src/proto/inspircd.rs
@@ -81,6 +81,23 @@ impl Protocol for InspIrcd {
                 }
             }
             "QUIT" => vec![NetEvent::Quit { uid: source.unwrap_or_default() }],
+            // account-registration relay from an ircd:
+            // ACCTREGISTER <reqid> <origin> <kind> <account> <p2> :<p3>
+            "ACCTREGISTER" => {
+                let a: Vec<&str> = tokens.by_ref().take(5).collect();
+                if a.len() == 5 {
+                    vec![NetEvent::AccountRequest {
+                        reqid: a[0].to_string(),
+                        origin: a[1].to_string(),
+                        kind: a[2].to_string(),
+                        account: a[3].to_string(),
+                        p2: a[4].to_string(),
+                        p3: trailing(rest),
+                    }]
+                } else {
+                    vec![]
+                }
+            }
             _ => vec![NetEvent::Unknown { line: line.to_string() }],
         }
     }
@@ -105,6 +122,13 @@ impl Protocol for InspIrcd {
             NetAction::Notice { from, to, text } => {
                 vec![format!(":{} NOTICE {} :{}", from, to, text)]
             }
+            // ACCTREGRESULT <reqid> <kind> <account> <status> <code> :<message>
+            NetAction::AccountResponse { reqid, kind, account, status, code, message } => {
+                vec![self.from_us(format!(
+                    "ACCTREGRESULT {} {} {} {} {} :{}",
+                    reqid, kind, account, status, code, message
+                ))]
+            }
             NetAction::Raw(s) => vec![s.clone()],
         }
     }
diff --git a/src/proto/mod.rs b/src/proto/mod.rs
index 96ac572..4bdd21d 100644
--- a/src/proto/mod.rs
+++ b/src/proto/mod.rs
@@ -12,6 +12,8 @@ pub enum NetEvent {
     Privmsg { from: String, to: String, text: String },
     UserConnect { uid: String, nick: String },
     Quit { uid: String },
+    // An ircd relaying an IRCv3 account-registration request to us as the authority.
+    AccountRequest { reqid: String, origin: String, kind: String, account: String, p2: String, p3: String },
     Unknown { line: String },
 }
 
@@ -24,6 +26,7 @@ pub enum NetAction {
     IntroduceUser { uid: String, nick: String, ident: String, host: String, gecos: String },
     Privmsg { from: String, to: String, text: String },
     Notice { from: String, to: String, text: String },
+    AccountResponse { reqid: String, kind: String, account: String, status: String, code: String, message: String },
     Raw(String),
 }