diff --git a/cmd/lemcmd/lem.go b/cmd/lemcmd/lem.go
index 74886f0..d8556a3 100644
--- a/cmd/lemcmd/lem.go
+++ b/cmd/lemcmd/lem.go
@@ -19,6 +19,7 @@ func AddLEMCommands(root *cli.Command) {
 	addExportCommands(root)
 	addMonCommands(root)
 	addInfraCommands(root)
+	addSetupCommands(root)
 }
 
 // envOr returns the environment variable value, or the fallback if not set.
diff --git a/cmd/lemcmd/setup.go b/cmd/lemcmd/setup.go
new file mode 100644
index 0000000..8ae4709
--- /dev/null
+++ b/cmd/lemcmd/setup.go
@@ -0,0 +1,26 @@
+// setup.go — CLI registration for `lem setup` commands.
+package lemcmd
+
+import (
+	"forge.lthn.ai/core/cli/pkg/cli"
+	"forge.lthn.ai/lthn/lem/pkg/lem"
+)
+
+func addSetupCommands(root *cli.Command) {
+	setupGroup := cli.NewGroup("setup", "Setup commands", "Initialise LEM data and environment.")
+
+	var dataCfg lem.SetupOpts
+	dataCmd := cli.NewCommand("data", "Hydrate cold storage into DuckDB + InfluxDB", "",
+		func(cmd *cli.Command, args []string) error {
+			return lem.RunSetup(dataCfg)
+		},
+	)
+	cli.StringFlag(dataCmd, &dataCfg.Root, "root", "", ".", "LEM repo root directory")
+	cli.StringFlag(dataCmd, &dataCfg.DB, "db", "", "", "DuckDB path (defaults to LEM_DB env, then ./lem.duckdb)")
+	cli.StringFlag(dataCmd, &dataCfg.Influx, "influx", "", "", "InfluxDB URL (default http://10.69.69.165:8181)")
+	cli.StringFlag(dataCmd, &dataCfg.InfluxDB, "influx-db", "", "", "InfluxDB database (default training)")
+	cli.BoolFlag(dataCmd, &dataCfg.SkipInflux, "skip-influx", "", false, "Skip InfluxDB backfill")
+	setupGroup.AddCommand(dataCmd)
+
+	root.AddCommand(setupGroup)
+}