diff --git a/core/grammar/eval.ml b/core/grammar/eval.ml
index bac2295e5..9561405bb 100644
--- a/core/grammar/eval.ml
+++ b/core/grammar/eval.ml
@@ -513,6 +513,7 @@ let compile_inits ~debug_mode ~warning ?rescale ~compile_mode_on contact_map env
               LKappa.r_rate = Alg_expr.const Nbr.zero;
               LKappa.r_un_rate = None;
               LKappa.r_edit_style = true;
+              LKappa.r_guard = None;
             }
           in
           let preenv'', state' =
@@ -544,6 +545,7 @@ let compile_inits ~debug_mode ~warning ?rescale ~compile_mode_on contact_map env
               LKappa.r_rate = Alg_expr.const Nbr.zero;
               LKappa.r_un_rate = None;
               LKappa.r_edit_style = false;
+              LKappa.r_guard = None;
             }
           in
           (match
diff --git a/core/grammar/lKappa_compiler.ml b/core/grammar/lKappa_compiler.ml
index dd88fa55a..bdb78b93d 100644
--- a/core/grammar/lKappa_compiler.ml
+++ b/core/grammar/lKappa_compiler.ml
@@ -1345,6 +1345,7 @@ let assemble_rule ~warning ~syntax_version (rule : rule_inter_rep)
     r_delta_tokens;
     r_rate;
     r_un_rate;
+    r_guard = rule.guard;
   }
 
 let modif_expr_of_ast ~warning ~syntax_version sigs counters_info tok algs
diff --git a/core/symmetries/patterns_extra.ml b/core/symmetries/patterns_extra.ml
index dd35b4989..b24abd3ff 100644
--- a/core/symmetries/patterns_extra.ml
+++ b/core/symmetries/patterns_extra.ml
@@ -573,6 +573,7 @@ let lkappa_init =
     LKappa.r_rate = Alg_expr.int 0;
     LKappa.r_un_rate = None;
     LKappa.r_edit_style = true;
+    LKappa.r_guard = None;
   }
 
 let raw_mixture_to_lkappa_rule raw_mixture =
@@ -583,6 +584,7 @@ let raw_mixture_to_lkappa_rule raw_mixture =
     LKappa.r_rate = Alg_expr.int 0;
     LKappa.r_un_rate = None;
     LKappa.r_edit_style = true;
+    LKappa.r_guard = None;
   }
 
 let rule_mixture_to_lkappa_rule rule_mixture =
@@ -593,6 +595,7 @@ let rule_mixture_to_lkappa_rule rule_mixture =
     LKappa.r_rate = Alg_expr.int 0;
     LKappa.r_un_rate = None;
     LKappa.r_edit_style = true;
+    LKappa.r_guard = None;
   }
 
 (*convert a species into lkappa rule signature*)
diff --git a/core/term/lKappa.ml b/core/term/lKappa.ml
index 19fe64518..37119d709 100644
--- a/core/term/lKappa.ml
+++ b/core/term/lKappa.ml
@@ -36,6 +36,14 @@ type rule_agent = {
 
 type rule_mixture = rule_agent list
 
+type 'id guard =
+  | True
+  | False
+  | Param of 'id
+  | Not of 'id guard
+  | And of 'id guard * 'id guard
+  | Or of 'id guard * 'id guard
+
 type rule = {
   r_mix: rule_mixture;
   r_created: Raw_mixture.t;
@@ -46,16 +54,9 @@ type rule = {
     * (rule_mixture, int) Alg_expr.e Loc.annoted option)
     option;
   r_edit_style: bool;
+  r_guard: string guard option;
 }
 
-type 'id guard =
-  | True
-  | False
-  | Param of 'id
-  | Not of 'id guard
-  | And of 'id guard * 'id guard
-  | Or of 'id guard * 'id guard
-
 let print_link pr_port pr_type pr_annot f = function
   | ANY_FREE -> Format.pp_print_string f "#"
   | LNK_TYPE (p, a) -> Format.fprintf f "%a.%a" (pr_port a) p pr_type a
@@ -508,8 +509,22 @@ let print_rates ~noCounters sigs counters_info pr_tok pr_var f r =
                  md))
           max_dist)
 
+let rec print_guard f g =
+  (*rTODO test*)
+  match g with
+  | True -> Format.fprintf f "TRUE"
+  | False -> Format.fprintf f "FALSE"
+  | Param i -> Format.fprintf f "%s" i
+  | And (a, b) -> Format.fprintf f "@[%a && %a@]" print_guard a print_guard b
+  | Or (a, b) -> Format.fprintf f "@[(%a || %a)@]" print_guard a print_guard b
+  | Not a -> Format.fprintf f "@[[not] %a@]" print_guard a
+
 let print_rule ~noCounters ~full sigs counters_info pr_tok pr_var f r =
-  Format.fprintf f "@[<h>%t%t%a%t@]"
+  Format.fprintf f "@[<h>%t%t%t%a%t@]"
+    (fun f ->
+      match r.r_guard with
+      | None -> ()
+      | Some g -> print_guard f g)
     (fun f ->
       if full || r.r_edit_style then
         Format.fprintf f "%a%a"
@@ -679,6 +694,7 @@ let rule_of_json ~filenames = function
                 (List.assoc "unary_rate" l)
             with Not_found -> None);
          r_edit_style = Yojson.Basic.Util.to_bool (List.assoc "edit_style" l);
+         r_guard = None (*TODO List.assoc_opt "guard" l;*);
        }
      with Not_found ->
        raise (Yojson.Basic.Util.Type_error ("Incorrect rule", x)))
diff --git a/core/term/lKappa.mli b/core/term/lKappa.mli
index 112a44417..aea61f6f6 100644
--- a/core/term/lKappa.mli
+++ b/core/term/lKappa.mli
@@ -51,6 +51,14 @@ Array.copy ra_ints)]. *)
 type rule_mixture = rule_agent list
 (** [rule_mixture] is the mixture description from the initial state of a rule *)
 
+type 'id guard =
+  | True
+  | False
+  | Param of 'id
+  | Not of 'id guard
+  | And of 'id guard * 'id guard
+  | Or of 'id guard * 'id guard
+
 type rule = {
   r_mix: rule_mixture;  (** Initial mixture state *)
   r_created: Raw_mixture.t;  (** Mixture state after rule is applied *)
@@ -62,16 +70,10 @@ type rule = {
     option;
   r_edit_style: bool;
       (** If rule was written in edit style, else it's rewrite style *)
+  r_guard: string guard option;
+      (** There could be a guard that defines if this rule is active or not. *)
 }
 
-type 'id guard =
-  | True
-  | False
-  | Param of 'id
-  | Not of 'id guard
-  | And of 'id guard * 'id guard
-  | Or of 'id guard * 'id guard
-
 val agent_to_erased : Signature.s -> rule_agent -> rule_agent
 val to_erased : Signature.s -> rule_mixture -> rule_mixture
 val to_maintained : rule_mixture -> rule_mixture
@@ -132,6 +134,8 @@ val print_rates :
   rule ->
   unit
 
+val print_guard : Format.formatter -> string guard -> unit
+
 val print_rule :
   noCounters:bool ->
   full:bool ->