diff --git a/libasn1parser/asn1p_param.c b/libasn1parser/asn1p_param.c
new file mode 100644
index 0000000..f708224
--- /dev/null
+++ b/libasn1parser/asn1p_param.c
@@ -0,0 +1,111 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+
+#include "asn1parser.h"
+
+/*
+ * Construct a new empty parameters list.
+ */
+asn1p_paramlist_t *
+asn1p_paramlist_new(int _lineno) {
+	asn1p_paramlist_t *pl;
+
+	pl = calloc(1, sizeof *pl);
+	if(pl) {
+		pl->_lineno = _lineno;
+	}
+
+	return pl;
+}
+
+void
+asn1p_paramlist_free(asn1p_paramlist_t *pl) {
+	if(pl) {
+		if(pl->params) {
+			int i = pl->params_count;
+			while(i--) {
+				if(pl->params[i].governor)
+					asn1p_ref_free(pl->params[i].governor);
+				if(pl->params[i].argument)
+					free(pl->params[i].argument);
+				pl->params[i].governor = 0;
+				pl->params[i].argument = 0;
+			}
+			free(pl->params);
+			pl->params = 0;
+		}
+
+		free(pl);
+	}
+}
+
+int
+asn1p_paramlist_add_param(asn1p_paramlist_t *pl, asn1p_ref_t *gov, char *arg) {
+
+	if(!pl || !arg) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	/*
+	 * Make sure there's enough space to insert a new element.
+	 */
+	if(pl->params_count == pl->params_size) {
+		int newsize = pl->params_size?pl->params_size<<2:4;
+		void *p;
+		p = realloc(pl->params,
+			newsize * sizeof(pl->params[0]));
+		if(p) {
+			pl->params = p;
+			pl->params_size = newsize;
+		} else {
+			return -1;
+		}
+
+	}
+
+	if(gov) {
+		pl->params[pl->params_count].governor = asn1p_ref_clone(gov);
+		if(pl->params[pl->params_count].governor == NULL) {
+			return -1;
+		}
+	} else {
+		pl->params[pl->params_count].governor = 0;
+	}
+
+	pl->params[pl->params_count].argument = strdup(arg);
+	if(pl->params[pl->params_count].argument) {
+		pl->params_count++;
+		return 0;
+	} else {
+		if(pl->params[pl->params_count].governor)
+			asn1p_ref_free(pl->params[pl->params_count].governor);
+		return -1;
+	}
+}
+
+asn1p_paramlist_t *
+asn1p_paramlist_clone(asn1p_paramlist_t *pl) {
+	asn1p_paramlist_t *newpl;
+
+	newpl = asn1p_paramlist_new(pl->_lineno);
+	if(newpl) {
+		int i;
+		for(i = 0; i < pl->params_count; i++) {
+			if(asn1p_paramlist_add_param(newpl,
+				pl->params[i].governor,
+				pl->params[i].argument
+			)) {
+				asn1p_paramlist_free(newpl);
+				newpl = NULL;
+				break;
+			}
+		}
+	}
+
+	return newpl;
+}
+