diff --git a/src/logging.rs b/src/logging.rs
new file mode 100644
index 0000000..9981053
--- /dev/null
+++ b/src/logging.rs
@@ -0,0 +1,136 @@
+use log::kv;
+use std::fmt::Write as _;
+use std::io::Write as _;
+use std::sync;
+
+type SyslogLogger = syslog::Logger<syslog::LoggerBackend, syslog::Formatter3164>;
+
+/// A syslog logger which preserves the key-values supplied to `log!` macros.
+///
+/// `syslog::BasicLogger` currently formats only `Record::args()`, silently
+/// dropping `Record::key_values()`.  Keep the traditional RFC 3164 transport
+/// and put the fields in the message body so existing syslog deployments keep
+/// working.
+pub struct KvLogger {
+    logger: sync::Arc<sync::Mutex<SyslogLogger>>,
+}
+
+impl KvLogger {
+    fn new(logger: SyslogLogger) -> Self {
+        Self {
+            logger: sync::Arc::new(sync::Mutex::new(logger)),
+        }
+    }
+}
+
+impl log::Log for KvLogger {
+    fn enabled(&self, metadata: &log::Metadata<'_>) -> bool {
+        metadata.level() <= log::max_level() && metadata.level() <= log::STATIC_MAX_LEVEL
+    }
+
+    fn log(&self, record: &log::Record<'_>) {
+        if !self.enabled(record.metadata()) {
+            return;
+        }
+
+        let message = format_message(record);
+        let Ok(mut logger) = self.logger.lock() else {
+            return;
+        };
+
+        let result = match record.level() {
+            log::Level::Error => logger.err(message),
+            log::Level::Warn => logger.warning(message),
+            log::Level::Info => logger.info(message),
+            log::Level::Debug | log::Level::Trace => logger.debug(message),
+        };
+        let _ = result;
+    }
+
+    fn flush(&self) {
+        if let Ok(mut logger) = self.logger.lock() {
+            let _ = logger.backend.flush();
+        }
+    }
+}
+
+struct FieldVisitor {
+    fields: String,
+}
+
+impl<'kvs> kv::VisitSource<'kvs> for FieldVisitor {
+    fn visit_pair(&mut self, key: kv::Key<'kvs>, value: kv::Value<'kvs>) -> Result<(), kv::Error> {
+        if !self.fields.is_empty() {
+            self.fields.push(' ');
+        }
+        let _ = write!(self.fields, "{}={}", key.as_str(), value);
+        Ok(())
+    }
+}
+
+fn format_message(record: &log::Record<'_>) -> String {
+    let mut message = record.args().to_string();
+    let mut visitor = FieldVisitor {
+        fields: String::new(),
+    };
+
+    if let Err(error) = record.key_values().visit(&mut visitor) {
+        if !visitor.fields.is_empty() {
+            message.push(' ');
+        }
+        let _ = write!(message, "kv_error={error}");
+    }
+
+    if !visitor.fields.is_empty() {
+        message.push(' ');
+        message.push_str(&visitor.fields);
+    }
+    message
+}
+
+pub fn init_syslog(facility: syslog::Facility, log_level: log::LevelFilter) -> syslog::Result<()> {
+    let formatter = syslog::Formatter3164 {
+        facility,
+        hostname: None,
+        process: "sessiond-uaccess".to_owned(),
+        pid: std::process::id(),
+    };
+
+    let logger = if let Ok(logger) = syslog::unix(formatter.clone()) {
+        logger
+    } else if let Ok(logger) = syslog::tcp(formatter.clone(), ("127.0.0.1", 601)) {
+        logger
+    } else {
+        syslog::udp(formatter, ("0.0.0.0", 0), ("127.0.0.1", 514))?
+    };
+
+    log::set_boxed_logger(Box::new(KvLogger::new(logger)))
+        .map_err(|error| syslog::Error::Initialization(Box::new(error)))?;
+    log::set_max_level(log_level);
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::format_message;
+
+    #[test]
+    fn includes_key_values_after_message() {
+        let record = log::Record::builder()
+            .args(format_args!("session added"))
+            .key_values(&[("session_id", 42)])
+            .build();
+
+        assert_eq!(format_message(&record), "session added session_id=42");
+    }
+
+    #[test]
+    fn supports_values_with_spaces() {
+        let record = log::Record::builder()
+            .args(format_args!("assigned"))
+            .key_values(&[("seat", "seat 1")])
+            .build();
+
+        assert_eq!(format_message(&record), "assigned seat=seat 1");
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index c5c58f1..d3e8e6e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,6 +6,7 @@ mod session_core_v1 {
 
 mod config;
 mod ecs;
+mod logging;
 mod session;
 
 use anyhow::Context;
@@ -336,11 +337,7 @@ fn main() -> anyhow::Result<()> {
                 .init();
         }
         LogTarget::Syslog => {
-            syslog::init(
-                syslog::Facility::LOG_DAEMON,
-                log_level,
-                Some("sessiond-uaccess"),
-            )?;
+            logging::init_syslog(syslog::Facility::LOG_DAEMON, log_level)?;
         }
     }