diff --git a/include/config.h b/include/config.h
index 3bdbdb7b..6b48063a 100644
--- a/include/config.h
+++ b/include/config.h
@@ -66,6 +66,7 @@ struct sway_config {
 	list_t *cmd_queue;
 	list_t *workspace_outputs;
 	list_t *output_configs;
+	list_t *criteria;
 	struct sway_mode *current_mode;
 	uint32_t floating_mod;
 	enum swayc_layouts default_orientation;
diff --git a/include/criteria.h b/include/criteria.h
new file mode 100644
index 00000000..5c71d172
--- /dev/null
+++ b/include/criteria.h
@@ -0,0 +1,36 @@
+#ifndef _SWAY_CRITERIA_H
+#define _SWAY_CRITERIA_H
+
+#include "container.h"
+#include "list.h"
+
+/**
+ * Maps criteria (as a list of criteria tokens) to a command list.
+ *
+ * A list of tokens together represent a single criteria string (e.g.
+ * '[class="abc" title="xyz"]' becomes two criteria tokens).
+ *
+ * for_window: Views matching all criteria will have the bound command list
+ * executed on them.
+ *
+ * Set via `for_window <criteria> <cmd list>`.
+ */
+struct criteria {
+	list_t *tokens; // struct crit_token, contains compiled regex.
+	char *crit_raw; // entire criteria string (for logging)
+
+	char *cmdlist;
+};
+
+int criteria_cmp(const void *item, const void *data);
+void free_criteria(struct criteria *crit);
+
+// Pouplate list with crit_tokens extracted from criteria string, returns error
+// string or NULL if successful.
+char *extract_crit_tokens(list_t *tokens, const char *criteria);
+
+// Returns list of criteria that match given container. These criteria have
+// been set with `for_window` commands and have an associated cmdlist.
+list_t *criteria_for(swayc_t *cont);
+
+#endif
diff --git a/sway.5.txt b/sway.5.txt
index 5e9dbb1e..700de8b2 100644
--- a/sway.5.txt
+++ b/sway.5.txt
@@ -68,6 +68,10 @@ Commands
 **fullscreen**::
 	Toggles fullscreen status for the focused view.
 
+**for_window** <criteria> <command>::
+	Whenever a window that matches _criteria_ appears, run list of commands. See
+	**Criteria** section below.
+
 **gaps** edge_gaps <on|off|toggle>::
 	Whether or not to add gaps between views and workspace edges if amount of
 	inner gap is not zero. When _no_, no gap is added where the view is aligned to
@@ -175,3 +179,34 @@ Commands
 **workspace** <name> output <output>::
 	Specifies that the workspace named _name_ should appear on the specified
 	_output_.
+
+Criteria
+--------
+
+A criteria is a string in the form of e.g.:
+
+	[class="[Rr]egex.*" title="some title"]
+
+The string contains one or more (space separated) attribute/value pairs and they
+are used by some commands filter which views to execute actions on. All attributes
+must match for the criteria string to match.
+
+Currently supported attributes:
+
+**class**::
+	Compare value against the window class. Can be a regular expression. If value
+	is _focused_ then the window class must be the same as that of the currently
+	focused window.
+
+**id**::
+	Compare value against the app id. Can be a regular expression.
+
+**title**::
+	Compare against the window title. Can be a regular expression. If value is
+	_focused_ then the window title must be the same as that of the currently
+	focused window.
+
+**workspace**::
+	Compare against the workspace name for this view. Can be a regular expression.
+	If value is _focused_ then all the views on the currently focused workspace
+	matches.
diff --git a/sway/commands.c b/sway/commands.c
index 42105d5f..6a4af43c 100644
--- a/sway/commands.c
+++ b/sway/commands.c
@@ -23,6 +23,7 @@
 #include "sway.h"
 #include "resize.h"
 #include "input_state.h"
+#include "criteria.h"
 
 typedef struct cmd_results *sway_cmd(int argc, char **argv);
 
@@ -41,6 +42,7 @@ static sway_cmd cmd_floating;
 static sway_cmd cmd_floating_mod;
 static sway_cmd cmd_focus;
 static sway_cmd cmd_focus_follows_mouse;
+static sway_cmd cmd_for_window;
 static sway_cmd cmd_fullscreen;
 static sway_cmd cmd_gaps;
 static sway_cmd cmd_kill;
@@ -1241,6 +1243,37 @@ static struct cmd_results *cmd_log_colors(int argc, char **argv) {
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }
 
+static struct cmd_results *cmd_for_window(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "for_window", EXPECTED_AT_LEAST, 2))) {
+		return error;
+	}
+	// add command to a criteria/command pair that is run against views when they appear.
+	char *criteria = argv[0], *cmdlist = join_args(argv + 1, argc - 1);
+
+	struct criteria *crit = malloc(sizeof(struct criteria));
+	crit->crit_raw = strdup(criteria);
+	crit->cmdlist = cmdlist;
+	crit->tokens = create_list();
+	char *err_str = extract_crit_tokens(crit->tokens, crit->crit_raw);
+
+	if (err_str) {
+		error = cmd_results_new(CMD_INVALID, "for_window", err_str);
+		free(err_str);
+		free_criteria(crit);
+	} else if (crit->tokens->length == 0) {
+		error = cmd_results_new(CMD_INVALID, "for_window", "Found no name/value pairs in criteria");
+		free_criteria(crit);
+	} else if (list_seq_find(config->criteria, criteria_cmp, crit) != -1) {
+		sway_log(L_DEBUG, "for_window: Duplicate, skipping.");
+		free_criteria(crit);
+	} else {
+		sway_log(L_DEBUG, "for_window: '%s' -> '%s' added", crit->crit_raw, crit->cmdlist);
+		list_add(config->criteria, crit);
+	}
+	return error ? error : cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}
+
 static struct cmd_results *cmd_fullscreen(int argc, char **argv) {
 	struct cmd_results *error = NULL;
 	if (config->reading) return cmd_results_new(CMD_FAILURE, "fullscreen", "Can't be used in config file.");
@@ -1353,6 +1386,7 @@ static struct cmd_handler handlers[] = {
 	{ "floating_modifier", cmd_floating_mod },
 	{ "focus", cmd_focus },
 	{ "focus_follows_mouse", cmd_focus_follows_mouse },
+	{ "for_window", cmd_for_window },
 	{ "fullscreen", cmd_fullscreen },
 	{ "gaps", cmd_gaps },
 	{ "kill", cmd_kill },
diff --git a/sway/config.c b/sway/config.c
index 13865058..fc21b2a9 100644
--- a/sway/config.c
+++ b/sway/config.c
@@ -10,6 +10,7 @@
 #include "config.h"
 #include "layout.h"
 #include "input_state.h"
+#include "criteria.h"
 
 struct sway_config *config = NULL;
 
@@ -66,6 +67,11 @@ static void free_config(struct sway_config *config) {
 	}
 	list_free(config->workspace_outputs);
 
+	for (i = 0; i < config->criteria->length; ++i) {
+		free_criteria(config->criteria->items[i]);
+	}
+	list_free(config->criteria);
+
 	for (i = 0; i < config->output_configs->length; ++i) {
 		free_output_config(config->output_configs->items[i]);
 	}
@@ -82,6 +88,7 @@ static void config_defaults(struct sway_config *config) {
 	config->symbols = create_list();
 	config->modes = create_list();
 	config->workspace_outputs = create_list();
+	config->criteria = create_list();
 	config->output_configs = create_list();
 
 	config->cmd_queue = create_list();
diff --git a/sway/criteria.c b/sway/criteria.c
new file mode 100644
index 00000000..51779590
--- /dev/null
+++ b/sway/criteria.c
@@ -0,0 +1,349 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <regex.h>
+#include "criteria.h"
+#include "stringop.h"
+#include "list.h"
+#include "log.h"
+#include "container.h"
+#include "config.h"
+
+enum criteria_type { // *must* keep in sync with criteria_strings[]
+	CRIT_CLASS,
+	CRIT_ID,
+	CRIT_INSTANCE,
+	CRIT_TITLE,
+	CRIT_URGENT,
+	CRIT_WINDOW_ROLE,
+	CRIT_WINDOW_TYPE,
+	CRIT_WORKSPACE,
+	CRIT_LAST
+};
+
+// this *must* match the ordering in criteria_type enum
+static const char * const criteria_strings[] = {
+	"class",
+	"id",
+	"instance",
+	"title",
+	"urgent", // either "latest" or "oldest" ...
+	"window_role",
+	"window_type",
+	"workspace"
+};
+
+/**
+ * A single criteria token (ie. value/regex pair),
+ * e.g. 'class="some class regex"'.
+ */
+struct crit_token {
+	enum criteria_type type;
+	regex_t *regex;
+	char *raw;
+};
+
+static void free_crit_token(struct crit_token *crit) {
+	if (crit->regex) {
+		regfree(crit->regex);
+		free(crit->regex);
+	}
+	if (crit->raw) {
+		free(crit->raw);
+	}
+	free(crit);
+}
+
+static void free_crit_tokens(list_t *crit_tokens) {
+	for (int i = 0; i < crit_tokens->length; i++) {
+		free_crit_token(crit_tokens->items[i]);
+	}
+	list_free(crit_tokens);
+}
+
+// Extracts criteria string from its brackets. Returns new (duplicate)
+// substring.
+static char *criteria_from(const char *arg) {
+	char *criteria = NULL;
+	if (*arg == '[') {
+		criteria = strdup(arg + 1);
+	} else {
+		criteria = strdup(arg);
+	}
+
+	int last = strlen(criteria) - 1;
+	if (criteria[last] == ']') {
+		criteria[last] = '\0';
+	}
+	return criteria;
+}
+
+// Return instances of c found in str.
+static int countchr(char *str, char c) {
+	int found = 0;
+	for (int i = 0; str[i]; i++) {
+		if (str[i] == c) {
+			++found;
+		}
+	}
+	return found;
+}
+
+// criteria_str is e.g. '[class="some class regex" instance="instance name"]'.
+//
+// Will create array of pointers in buf, where first is duplicate of given
+// string (must be freed) and the rest are pointers to names and values in the
+// base string (every other, naturally). argc will be populated with the length
+// of buf.
+//
+// Returns error string or NULL if successful.
+static char *crit_tokens(int *argc, char ***buf, const char * const criteria_str) {
+	sway_log(L_DEBUG, "Parsing criteria: '%s'", criteria_str);
+	char *base = criteria_from(criteria_str);
+	char *head = base;
+	char *namep = head; // start of criteria name
+	char *valp = NULL; // start of value
+
+	// We're going to place EOS markers where we need to and fill up an array
+	// of pointers to the start of each token (either name or value).
+	int pairs = countchr(base, '=');
+	int max_tokens = pairs * 2 + 1; // this gives us at least enough slots
+
+	char **argv = *buf = calloc(max_tokens, sizeof(char*));
+	argv[0] = base; // this needs to be freed by caller
+
+	*argc = 1; // uneven = name, even = value
+	while (*head && *argc < max_tokens) {
+		if (namep != head && *(head - 1) == '\\') {
+			// escaped character: don't try to parse this
+		} else if (*head == '=' && namep != head) {
+			if (*argc % 2 != 1) {
+				// we're not expecting a name
+				return strdup("Unable to parse criteria: "
+					"Found out of place equal sign");
+			} else {
+				// name ends here
+				char *end = head; // don't want to rewind the head
+				while (*(end - 1) == ' ') {
+					--end;
+				}
+				*end = '\0';
+				if (*(namep) == ' ') {
+					namep = strrchr(namep, ' ') + 1;
+				}
+				argv[(*argc)++] = namep;
+			}
+		} else if (*head == '"') {
+			if (*argc % 2 != 0) {
+				// we're not expecting a value
+				return strdup("Unable to parse criteria: "
+					"Found quoted value where it was not expected");
+			} else if (!valp) { // value starts here
+				valp = head + 1;
+			} else {
+				// value ends here
+				argv[(*argc)++] = valp;
+				*head = '\0';
+				valp = NULL;
+				namep = head + 1;
+			}
+		} else if (*argc % 2 == 0 && !valp && *head != ' ') {
+			// We're expecting a quoted value, haven't found one yet, and this
+			// is not an empty space.
+			return strdup("Unable to parse criteria: "
+				"Names must be unquoted, values must be quoted");
+		}
+		head++;
+	}
+	return NULL;
+}
+
+// Returns error string on failure or NULL otherwise.
+static char *parse_criteria_name(enum criteria_type *type, char *name) {
+	*type = CRIT_LAST;
+	for (int i = 0; i < CRIT_LAST; i++) {
+		if (strcmp(criteria_strings[i], name) == 0) {
+			*type = (enum criteria_type) i;
+			break;
+		}
+	}
+	if (*type == CRIT_LAST) {
+		const char *fmt = "Criteria type '%s' is invalid or unsupported.";
+		int len = strlen(name) + strlen(fmt) - 1;
+		char *error = malloc(len);
+		snprintf(error, len, fmt, name);
+		return error;
+	} else if (*type == CRIT_INSTANCE || *type == CRIT_URGENT ||
+			*type == CRIT_WINDOW_ROLE || *type == CRIT_WINDOW_TYPE) {
+
+		// (we're just being helpful here)
+		const char *fmt = "\"%s\" criteria currently unsupported, "
+			"no window will match this";
+		int len = strlen(fmt) + strlen(name) - 1;
+		char *error = malloc(len);
+		snprintf(error, len, fmt, name);
+		return error;
+	}
+	return NULL;
+}
+
+// Returns error string on failure or NULL otherwise.
+static char *generate_regex(regex_t **regex, char *value) {
+	*regex = calloc(1, sizeof(regex_t));
+	int err = regcomp(*regex, value, REG_NOSUB);
+	if (err != 0) {
+		char *reg_err = malloc(64);
+		regerror(err, *regex, reg_err, 64);
+
+		const char *fmt = "Regex compilation (for '%s') failed: %s";
+		int len = strlen(fmt) + strlen(value) + strlen(reg_err) - 3;
+		char *error = malloc(len);
+		snprintf(error, len, fmt, value, reg_err);
+		free(reg_err);
+		return error;
+	}
+	return NULL;
+}
+
+// Pouplate list with crit_tokens extracted from criteria string, returns error
+// string or NULL if successful.
+char *extract_crit_tokens(list_t *tokens, const char * const criteria) {
+	int argc;
+	char **argv = NULL, *error = NULL;
+	if ((error = crit_tokens(&argc, &argv, criteria))) {
+		goto ect_cleanup;
+	}
+	for (int i = 1; i + 1 < argc; i += 2) {
+		char* name = argv[i], *value = argv[i + 1];
+		struct crit_token *token = calloc(1, sizeof(struct crit_token));
+		token->raw = strdup(value);
+
+		if ((error = parse_criteria_name(&token->type, name))) {
+			free_crit_token(token);
+			goto ect_cleanup;
+		} else if (token->type == CRIT_URGENT || strcmp(value, "focused") == 0) {
+			sway_log(L_DEBUG, "%s -> \"%s\"", name, value);
+			list_add(tokens, token);
+		} else if((error = generate_regex(&token->regex, value))) {
+			free_crit_token(token);
+			goto ect_cleanup;
+		} else {
+			sway_log(L_DEBUG, "%s -> /%s/", name, value);
+			list_add(tokens, token);
+		}
+	}
+ect_cleanup:
+	free(argv[0]); // base string
+	free(argv);
+	return error;
+}
+
+// test a single view if it matches list of criteria tokens (all of them).
+static bool criteria_test(swayc_t *cont, list_t *tokens) {
+	if (cont->type != C_VIEW) {
+		return false;
+	}
+	int matches = 0;
+	for (int i = 0; i < tokens->length; i++) {
+		struct crit_token *crit = tokens->items[i];
+		switch (crit->type) {
+			case CRIT_CLASS:
+				if (!cont->class) {
+					// ignore
+				} else if (strcmp(crit->raw, "focused") == 0) {
+					swayc_t *focused = get_focused_view(&root_container);
+					if (focused->class && strcmp(cont->class, focused->class) == 0) {
+						matches++;
+					}
+				} else if (crit->regex && regexec(crit->regex, cont->class, 0, NULL, 0) == 0) {
+					matches++;
+				}
+				break;
+			case CRIT_ID:
+				if (!cont->app_id) {
+					// ignore
+				} else if (crit->regex && regexec(crit->regex, cont->app_id, 0, NULL, 0) == 0) {
+					matches++;
+				}
+				break;
+			case CRIT_INSTANCE:
+				break;
+			case CRIT_TITLE:
+				if (!cont->name) {
+					// ignore
+				} else if (strcmp(crit->raw, "focused") == 0) {
+					swayc_t *focused = get_focused_view(&root_container);
+					if (focused->name && strcmp(cont->name, focused->name) == 0) {
+						matches++;
+					}
+				} else if (crit->regex && regexec(crit->regex, cont->name, 0, NULL, 0) == 0) {
+					matches++;
+				}
+				break;
+			case CRIT_URGENT: // "latest" or "oldest"
+				break;
+			case CRIT_WINDOW_ROLE:
+				break;
+			case CRIT_WINDOW_TYPE:
+				// TODO wlc indeed exposes this information
+				break;
+			case CRIT_WORKSPACE: ;
+				swayc_t *cont_ws = swayc_parent_by_type(cont, C_WORKSPACE);
+				if (!cont_ws || !cont_ws->name) {
+					// ignore
+				} else if (strcmp(crit->raw, "focused") == 0) {
+					swayc_t *focused_ws = swayc_active_workspace();
+					if (focused_ws->name && strcmp(cont_ws->name, focused_ws->name) == 0) {
+						matches++;
+					}
+				} else if (crit->regex && regexec(crit->regex, cont_ws->name, 0, NULL, 0) == 0) {
+					matches++;
+				}
+				break;
+			default:
+				sway_abort("Invalid criteria type (%i)", crit->type);
+				break;
+		}
+	}
+	return matches == tokens->length;
+}
+
+int criteria_cmp(const void *a, const void *b) {
+	if (a == b) {
+		return 0;
+	} else if (!a) {
+		return -1;
+	} else if (!b) {
+		return 1;
+	}
+	const struct criteria *crit_a = a, *crit_b = b;
+	int cmp = lenient_strcmp(crit_a->cmdlist, crit_b->cmdlist);
+	if (cmp != 0) {
+		return cmp;
+	}
+	return lenient_strcmp(crit_a->crit_raw, crit_b->crit_raw);
+}
+
+void free_criteria(struct criteria *crit) {
+	if (crit->tokens) {
+		free_crit_tokens(crit->tokens);
+	}
+	if (crit->cmdlist) {
+		free(crit->cmdlist);
+	}
+	if (crit->crit_raw) {
+		free(crit->crit_raw);
+	}
+	free(crit);
+}
+
+list_t *criteria_for(swayc_t *cont) {
+	list_t *criteria = config->criteria, *matches = create_list();
+	for (int i = 0; i < criteria->length; i++) {
+		struct criteria *bc = criteria->items[i];
+		if (criteria_test(cont, bc->tokens)) {
+			list_add(matches, bc);
+		}
+	}
+	return matches;
+}
diff --git a/sway/handlers.c b/sway/handlers.c
index 28fa9564..267a8f3a 100644
--- a/sway/handlers.c
+++ b/sway/handlers.c
@@ -19,6 +19,7 @@
 #include "input_state.h"
 #include "resize.h"
 #include "extensions.h"
+#include "criteria.h"
 
 // Event should be sent to client
 #define EVENT_PASSTHROUGH false
@@ -172,6 +173,21 @@ static bool handle_view_created(wlc_handle handle) {
 		set_focused_container(newview);
 		swayc_t *output = swayc_parent_by_type(newview, C_OUTPUT);
 		arrange_windows(output, -1, -1);
+		// check if it matches for_window in config and execute if so
+		list_t *criteria = criteria_for(newview);
+		for (int i = 0; i < criteria->length; i++) {
+			struct criteria *crit = criteria->items[i];
+			sway_log(L_DEBUG, "for_window '%s' matches new view %p, cmd: '%s'",
+					crit->crit_raw, newview, crit->cmdlist);
+			struct cmd_results *res = handle_command(crit->cmdlist);
+			if (res->status != CMD_SUCCESS) {
+				sway_log(L_ERROR, "Command '%s' failed: %s", res->input, res->error);
+			}
+			free_cmd_results(res);
+			// view must be focused for commands to affect it, so always
+			// refocus in-between command lists
+			set_focused_container(newview);
+		}
 	}
 	return true;
 }